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The purpose of this course project is to acquire practical skills in analyzing the technological process, selecting automatic control means, calculating measuring circuits of instruments and control means, as well as teaching the student independence in solving engineering and technical problems of constructing automatic control circuits for various technological parameters.
Introduction
Automation is the use of a set of tools that allow production processes to be carried out without the direct participation of a person, but under his control. Automation of production processes leads to increased output, reduced costs and improved product quality, reduces the number of service personnel, increases the reliability and durability of machines, saves materials, improves working conditions and safety precautions.
Automation frees people from the need to directly control mechanisms. In an automated production process, the role of a person is reduced to setting up, adjusting, servicing automation equipment and monitoring their operation. If automation facilitates human physical labor, then automation aims to facilitate mental labor as well. The operation of automation equipment requires highly qualified technical personnel.
In terms of automation level, thermal power engineering occupies one of the leading positions among other industries. Thermal power plants are characterized by the continuity of the processes occurring in them. At the same time, the production of thermal and electrical energy at any given time must correspond to consumption (load). Almost all operations at thermal power plants are mechanized, and transient processes in them develop relatively quickly. This explains the high development of automation in thermal energy.
Automating parameters provides significant benefits:
1) ensures a reduction in the number of working personnel, i.e. increasing his labor productivity,
2) leads to a change in the nature of work of service personnel,
3) increases the accuracy of maintaining the parameters of the generated steam,
4) increases labor safety and equipment reliability,
5) increases the efficiency of the steam generator.
Automation of steam generators includes automatic regulation, remote control, technological protection, thermal control, technological interlocks and alarms.
Automatic regulation ensures the progress of continuously occurring processes in the steam generator (water supply, combustion, steam superheating, etc.)
Remote control allows the personnel on duty to start and stop the steam generator unit, as well as switch and regulate its mechanisms at a distance, from the console where the control devices are located.
Thermal control over the operation of the steam generator and equipment is carried out using indicating and recording instruments that operate automatically. The devices continuously monitor the processes occurring in the steam generator plant, or are connected to the measurement object by service personnel or an information computer. Thermal control devices are placed on panels and control panels, as convenient as possible for observation and maintenance.
Technological interlocks perform a number of operations in a given sequence when starting and stopping the mechanisms of a steam generator plant, as well as in cases where technological protection is triggered. Interlocks eliminate incorrect operations when servicing a steam generator unit and ensure that equipment is switched off in the required sequence in the event of an emergency.
Process alarm devices inform the personnel on duty about the state of the equipment (in operation, stopped, etc.), warn that a parameter is approaching a dangerous value, and report the occurrence of an emergency condition of the steam generator and its equipment. Sound and light alarms are used.
The operation of boilers must ensure reliable and efficient production of steam of the required parameters and safe working conditions for personnel. To meet these requirements, operation must be carried out in strict accordance with laws, rules, norms and guidelines, in particular, in accordance with the “Rules for the design and safe operation of steam boilers” of Gosgortekhnadzor, “Rules for the technical operation of power plants and networks”, “Rules for technical operation of heat-using installations and heating networks".
1. Description of the technological process
A steam boiler is a complex of units designed to produce water steam. This complex consists of a number of heat exchange devices interconnected and used to transfer heat from fuel combustion products to water and steam. The initial carrier of energy, the presence of which is necessary for the formation of steam from water, is fuel.
The main elements of the work process carried out in a boiler plant are:
1) fuel combustion process,
2) the process of heat exchange between combustion products or the burning fuel itself with water,
3) the process of vaporization, consisting of heating water, evaporating it and heating the resulting steam.
During operation, two flows interact with each other are formed in boiler units: the flow of the working fluid and the flow of the coolant formed in the furnace.
As a result of this interaction, steam of a given pressure and temperature is obtained at the output of the object.
One of the main tasks that arises during the operation of a boiler unit is to ensure equality between the energy produced and consumed. In turn, the processes of steam formation and energy transfer in the boiler unit are uniquely related to the amount of substance in the flows of the working fluid and coolant.
Fuel combustion is a continuous physical and chemical process. The chemical side of combustion is the process of oxidation of its combustible elements with oxygen, which takes place at a certain temperature and is accompanied by the release of heat. The intensity of combustion, as well as the efficiency and stability of the fuel combustion process, depend on the method of supplying and distributing air between the fuel particles. Conventionally, the fuel combustion process is divided into three stages: ignition, combustion and afterburning. These stages generally occur sequentially in time and partially overlap one another.
Calculation of the combustion process usually comes down to determining the amount of air per m3 required for the combustion of a unit mass or volume of fuel, the amount and composition of the heat balance and determining the combustion temperature.
The meaning of heat transfer is the heat transfer of thermal energy released during fuel combustion to water, from which it is necessary to obtain steam, or steam, if it is necessary to increase its temperature above the saturation temperature. The heat exchange process in the boiler occurs through water-gas-tight heat-conducting walls called the heating surface. Heating surfaces are made in the form of pipes. Inside the pipes there is a continuous circulation of water, and outside they are washed by hot flue gases or receive thermal energy by radiation. Thus, all types of heat transfer take place in the boiler unit: thermal conductivity, convection and radiation. Accordingly, the heating surface is divided into convective and radiation. The amount of heat transferred through a unit heating area per unit time is called the thermal stress of the heating surface. The magnitude of the voltage is limited, firstly, by the properties of the heating surface material, and secondly, by the maximum possible intensity of heat transfer from the hot coolant to the surface, from the heating surface to the cold coolant.
The intensity of the heat transfer coefficient is higher, the higher the temperature difference of the coolants, the speed of their movement relative to the heating surface, and the higher the cleanliness of the surface.
The formation of steam in boiler units occurs in a certain sequence. Steam formation begins already in the screen pipes. This process takes place at high temperatures and pressures. The phenomenon of evaporation is that individual molecules of a liquid, located near its surface and possessing high speeds, and therefore greater kinetic energy compared to other molecules, overcoming the force effects of neighboring molecules, creating surface tension, fly out into the surrounding space. With increasing temperature, the intensity of evaporation increases. The reverse process of vaporization is called condensation. The liquid formed during condensation is called condensate. It is used to cool metal surfaces in superheaters.
The steam generated in the boiler unit is divided into saturated and superheated. Saturated steam is in turn divided into dry and wet. Since thermal power plants require superheated steam, a superheater is installed to superheat it, in which the heat obtained from the combustion of fuel and waste gases is used to superheat the steam. The resulting superheated steam at temperature T=540 C and pressure P=100 atm. goes for technological needs.
2. Technology for the production of thermal energy in boiler houses
Boiler installations in industry are intended to produce steam used in steam engines and in various technological processes, as well as for heating, ventilation and domestic needs.
Introduction
Introduction
The development of automation in the chemical industry is associated with the increasing intensification of technological processes and the growth of production, the use of units of large unit capacity, the complication of technological schemes, and the imposition of increased demands on the resulting products.
A technological process is understood as a set of technological operations carried out on raw materials in one or more apparatuses, the purpose of which is to obtain a product with specified properties; They are carried out in distillation columns, reactors, extractors, absorbers, dryers and other apparatus. Usually, in order to process chemicals and obtain target products from these devices, complex technological schemes are assembled.
The technological process implemented on the appropriate technological equipment is called technological control object. TOU is a separate apparatus, unit, installation, department, workshop, production, enterprise. Various external disturbing influences (changes in the consumption or composition of feedstock, the condition and characteristics of process equipment, etc.) disrupt the operation of the TOU. Therefore, in order to maintain its normal functioning, as well as if it is necessary to change its operating conditions, for example, in order to conduct a technological process according to a certain program or to obtain a target product of a different quality or composition, the technical equipment must be managed. Control- this is a targeted impact on an object, which ensures its optimal functioning and is quantitatively assessed by the value of the quality criterion (indicator). The criteria can be of a technological or economic nature (productivity of a process plant, cost of production, etc.). With automatic control, the impact on the object is carried out by a special automatic device in a closed loop; This combination of elements forms an automatic control system. A special case of management is regulation. Regulationcalled maintaining the output values of an object near the required constant or variable values in order to ensure the normal mode of its operation by applying control actions to the object. An automatic device that ensures that the output values of an object are maintained near the required values is called automatic regulator.
automatic control hydrocracking chemical 1. Process research
1.1 General characteristics of the production facility
Installations for hydrocracking, catalyst regeneration and hydrodearomatization of diesel fuel (RK and GDA) are designed to produce: 1.2 Description of the technological control object
The technological control object is the 10-DA-201 fractionation column, in which the liquid reaction products are separated into target fractions. The main raw material of the 10-DA-201 column is liquid from GSND 10-FA-201 (hydrogenate), heated in a 10-VA-201 furnace to 370-394°C. From the 10-VA-201 furnace, the raw material goes to the 6th tray of the 10-DA-201 column. Light raw materials from the 10-FA-202 separator after heat exchangers 10-EA-201, 10-EA-202, 10-EA-203 and 10-EA-204 with a temperature of 205-237 ° C are supplied to the 19th or 16th fractionation tray columns 10-DA-201 depending on the production of summer or winter type of diesel fuel. To strip and reduce the partial pressure of light hydrocarbon fractions, superheated medium-pressure steam with a temperature of no more than 390°C is supplied to the bottom of the fractionation column 10-DA-201 through a separator 10-FA-206. The steam flow into the column is regulated by a flow regulator 10-FICA-0067 with an alarm for low 2.5 t/h steam flow into the column 10-DA-201. Condensate from separator 10-FA-206 is discharged through a condensate trap into the condensate collector. The condensate level in the 10-FA-206 separator is controlled by the 10-LISA-0033 device with an alarm of 71% and blocking at an emergency high level of 79% for closing the valve 10-FV-0067 on the steam supply line to the column 10-DA-201. From the top of the fractionation column 10-DA-201 vapors of hydrocarbons, hydrogen sulfide, ammonia and water vapor with a temperature of 120-150°C and a pressure of 1.5-1.95 kgf/cm 2enter the air-cooled condenser 10-EC-202A I F. The temperature at the top of the column is controlled using a 10-TIСA-0143 device with an alarm for low temperatures of 120°C and high temperatures of 150°C. The vapor pressure at the top of the column is controlled using devices 10-PISA-0170, 10-PISA-0423A/B with a low alarm of 1 kgf/cm 2and high pressure 3 kgf/cm 2.
When an emergency high pressure of 3.5 kgf/cm is reached at the top of column 10-DA-201 2from two devices out of three 10-PISA-0170, 10-PISA-0423A/B, the blocking to stop the furnace 10-VA-201 is triggered: shutters 10-XV-0023, 10-XV-0024, valve 10-FV-0145 on the fuel gas supply line and shut-off valve 10-XV-0007 on the regeneration gas supply line to the furnace are closed, shutters 10-XV-0025, 10- are opened XV-0006 into the atmosphere; the flow regulator 10-FICA-0142A on the air supply line to the furnace is automatically reset from automatic to manual regulation and the valve 10-FV-0067 on the steam supply line to the fractionation column 10-DA-201 is closed. The temperature of the cube, feed zone, diesel fuel and kerosene extraction zones and the top of the 10-DA-201 column is controlled using devices 10-TI-0149, 10-TI-0148, 10-TI-0147, 10-TI-0146, 10-TI -0145, 10-TI-0144. The pressure drop between trays from 1 to 21 and from 21 to 32 in the height of column 10-DA-201 is monitored using devices 10-PDIA-0176, 10-PDIA-0173 with an alarm for a high difference of 0.3 kgf/cm 2.
The vapors leaving the top of the column enter the air-cooled condensers 10-EC-202A I F. Cooled and partially condensed vapor-gas mixture from air-cooled condensers 10-EC-202A I F with a temperature of 48-52°C, which is controlled by the 10-TI-0181 device, enters the annulus of water coolers 10-EA-205A/B, where it is cooled with circulating water, and with a temperature of 30-45°C, which is controlled carried out using devices 10-TIА-0183А/В, enters the separator 10-FA-203. From separator 10-FA-203 hydrocarbon gas with a temperature of 30-45°C and a pressure of 1.2-1.45 kgf/cm 2enters the 10-DA-207 low-pressure scrubber for hydrogen sulfide removal. The unstable gasoline that has condensed and separated from the water from the separator 10-FA-203 through the cut-off valve 10-HV-0119 enters the suction of the pump 10-GA-204A/S. The main part of unstable gasoline with a temperature of 35-45 ° C is returned as irrigation to the column 10-DA-201 on the 32nd plate by the pump 10-GA-204A/S through the flow regulator 10-FICA-0066 with an alarm at a low value of 32 t/h columns 10-DA-201. The balance amount of unstable gasoline is pumped through the 10-FIC-0095 flow regulator with correction according to the 10-LICSA-0037C level in the 10-FA-203 separator into the debutanizer 10-DA-204. Fractionation column 10-DA-201 has two blind trays 17 and 25 for selecting diesel and kerosene fractions. From the 25th blind plate of column 10-DA-201, the kerosene fraction with a temperature of 170-195°C is fed through the flow regulator 10-FIC-0072 into the stripper 10-DA-203 to the upper 6th plate for stripping light hydrocarbons. The temperature of the kerosene fraction before stripping 10-DA-203 is controlled using the 10-TI-0152 device. Light hydrocarbon vapors from the top of stripping 10-DA-203 with a pressure of 1.97 kgf/cm 2and a temperature of 165-210°C, which is controlled using the 10-TI-0158 device, are returned to 10-DA-201 under the 30th plate in 10-DA-201. The stripping cube 10-DA-203 is divided by a partition that ensures a constant level of kerosene fraction in the inter-tube space of the thermosiphon reboiler 10-EA-207. The kerosene fraction from the lower plate enters the bottom part of the stripper on the side of the flow outlet into the reboiler 10-EA-207. The steam-condensate mixture of 10-EA-207 with a temperature of 203-220°C is returned to the bottom part of the stripper. The temperature of the kerosene fraction streams before and after 10-EA-207 is controlled using devices 10-TI-0154, 10-TI-0155. The clarity of separation of the kerosene and unstable gasoline fractions is ensured by maintaining a set temperature between the 2nd and 3rd stripping plates 10-DA-203, adjusted by pressure from the 10-PI-0428 device. The diesel fraction from the 17th blind plate of column 10-DA-201 with a temperature of 244-295°C, which is monitored using the 10-TI-0151 device, is divided into two streams: the diesel circulation stream and the stream supplied to stripping. 10-DA-202. The circulating irrigation flow by the 10-GA-206A/S pump is supplied to the tube space of the 10-EA-202 heat exchanger, where, giving off heat to the light raw material of the fractionation column entering through the intertubular space, it is cooled and, at a temperature of 170-225°C, is supplied as circulating irrigation to the 21st plate in column 10-DA-201. The flow rate of circulation irrigation into the 10-DA-201 column in the amount of 110-130 t/h is regulated by the flow regulator 10-FIC-0057, the valve 10-FV-0057 of which is installed at the outlet of circulation irrigation from 10-EA-202. The temperature of the circulation irrigation into the column 10-DA-201 at the outlet of 10-EA-202 is regulated by the temperature controller 10-TIC-0125, the valve 10-TV-0125 of which is installed on the bypass of the heat exchanger 10-EA-202. The presence of liquid at the suction of 10-GA-206A/S pumps is monitored by a level switch 10-LS-0068 with a block to stop the 10-GA-206A/S pump due to lack of liquid. The main flow of the diesel fraction removed from column 10-DA-201 with a constant flow rate from 10-FIC-0076 through valve 10-FV-0076 is supplied for stripping light hydrocarbons to the upper 6th plate in stripping 10-DA-202. Light fraction vapors from the top of stripping 10-DA-202 with pressure up to 2.04 kgf/cm 2and a temperature of 246-252°C, which is controlled using the 10-TI-0160 device, and the GDA units from 10-DA-501 are returned under the blank 25th plate in 10-DA-201. The 10-DA-202 stripping cube is divided by a partition that ensures a constant level of diesel fraction and the creation of a driving force in the inter-tube space of the 10-EA-206 reboiler. The steam-condensate mixture of 10-EA-206 with a temperature of 250-293°C is returned to the bottom part of the stripper. From cube 10-DA-201 there is a gravity line for emergency release of the column through shut-off valve 10-HV-0157 into emergency discharge tank 10-FA-412. The level in the bottom of the 10-DA-201 column is regulated by the 10-LICА-0032 level regulator, valves 10-FV-0109, 10-FV-0112 of which are installed on the hot and cold gas oil output lines from the installation after the 10-EA-214A/B heat exchangers and 10-EC-203. The choice of level control in the cube of column 10-DA-201 from devices 10-LICSA-0032A and 10-LICSA-0032B is carried out using the selector 10-HS-0309, with signaling at a low level of 25% and a high level of 80% level. When an emergency low level of 7% is reached from the 10-LICSA-0032A/B devices, a block to stop the pump 10-GA-202A/S is triggered, and when an emergency high level of 93% is reached, a block to close the valve 10-FV-0067 on the supply line is triggered pair in column 10-DA-201. Commercial gas oil from the bottom of column 10-DA-201 with a temperature of 342-370°C is supplied through a cut-off valve 10-HV-0075 by a pump 10-GA-202A/S to reboilers 10-EA-206, 10-EA-207, 10-EA -506, from where the combined gas oil flow with a temperature of 328-358°C enters in two parallel flows into the annulus of heat exchangers 10-EA-217C/V/A and 10-EA-217F/E/D, where it heats the hydrocracking raw material. 2. Identification of the control object
To synthesize an ACP, it is necessary to know the mathematical model of the control object. The mathematical model of the control object was obtained by the method of active experiment. It consists of taking transient characteristics and determining the transfer function coefficients from them. The transient response is the solution of the differential equation of the system with a step input action and zero initial conditions. This characteristic, as a differential equation, characterizes the dynamic properties of a linear system (stationarity of object properties, linearity of the control object, concentration of object parameters). 2.1 Identification by reference channel
The transient response along the reference channel was removed after changing the position of the 10FV0076 valve from 40.4% to 42% opening. The object's response to disturbance was measured by a sensor at position 10TI0147 and recorded on the SCADA system. To identify the object, the Shimoyu integral area method will be used. To increase the accuracy of this method, the acceleration curve will be smoothed using the moving average method. Delay time: τз=25 min. 2.2 Identification of an object by disturbance channel
A sharp change in irrigation flow into column 10DA201, measured by the device at position 10FI0066, was chosen as a stepwise impact on the object through the disturbance channel. Such an impact can be considered stepwise with sufficient accuracy. Similar to identifying an object using a reference channel, to improve accuracy it is necessary to smooth out the transient response. Calculation of the object's transmission coefficient: Lag time: Object identification was performed in the LinReg program. As a result, the object model looks like: 3. Synthesis of the regulatory system
3.1 Synthesis of a single-loop temperature control system on the 17th tray of the 10DA201 fractionation column
The temperature in the column is controlled by changing the flow rate of diesel fuel discharge from the 17th plate. In this system, the irrigation flow into the column will be an external disturbance. A system with a PI regulator was considered as a single-circuit level control system. The calculation of the optimal settings of the PI regulator was carried out using the Rotach method V.Ya. using the LinReg program. PI controller settings: Ti=13.6.res=0.046 3.2 Synthesis of a single-circuit temperature control system on the 17th plate of the 10DA201 fractionation column with compensation for disturbance through the irrigation channel
One of the disturbances affecting the operation of the column is a change in the irrigation flow rate supplied under the 31 trays of the column. This disturbance is measurable, which makes it possible to create a system that compensates for this disturbance. The block diagram of such a system will take the form shown in Fig. 8. To ensure the condition of absolute invariance of the controlled quantity relative to the disturbance, the condition must be satisfied After substituting the real values of the transfer functions Wυ (s), Wµ (s) and Wp (s) we obtain This function cannot be implemented due to the presence of the e20s lead. It is impossible to achieve absolute invariance in such a system, so the problem should be solved with invariance up to ε. Let us determine the vector of this function at the most dangerous resonant frequency: WK (jwres) =-2.9+3.2i The CFC vector at the resonant frequency falls into the 2nd quadrant of the complex plane, so it makes sense to use a real second-order differentiating link as a device for inputting the influence of a disturbance, because its CFC is also partially in the 2nd quadrant. In general, the second order differentiating link has the form Neglecting the lead in the transfer function of the ideal compensating element, we obtain the transfer function of the compensator After analyzing the function in Matlab, we can conclude that the coefficient of the first power in the numerator is insignificant. Also neglecting the coefficients of the third degree (since they do not have a significant effect on the properties of the transfer function), we reduce the transfer function to the form of a real second-order differentiating link Fig.9 Adjustment of compensator coefficients. As a result, the transfer function of the compensator was obtained 4. Simulation of an automatic control system in the Simulink application of the MatLab package
4.1 Modeling an ideal ATS
Fig. 11 Testing the task of single-circuit ACS and ACS with disturbance compensation. Fig. 12 Testing the disturbance of a single-circuit ACS and an ACS with disturbance compensation. 4.2 Comparison of the operation of a single-circuit ACS and an ACS with disturbance compensation
Parameter Single-circuit ACS Single-circuit ACS with disturbance compensation By reference By disturbance By reference By disturbance Maximum surge 1,313,11,313,1 Regulation time, min 16924016995 Degree of attenuation 0,870,870,870,99 4.3 Simulation of a real ATS
The operation of a real system differs from the ideal one by some nonlinearities, such as insensitivity of sensors, limited stroke and backlash of the actuator. The following elements are used to model them: Deadzone - the block generates a zero output within the specified area, called the dead zone (measurement range*accuracy class*0.05=0.06; measurement range*accuracy class*0.05= - 0.06); Backlash - models the backlash present in the actuator ( Δy *0,05=0,5);
Saturate - nonlinear limiter element models the limitation of the actuator stroke (70; - 30); Fig. 13 Model of a real single-circuit ACS and a real ACS with disturbance compensation. 4.4 comparison of characteristics of ideal and real ATS
Fig. 14 Working out the task with an ideal and real system. Fig. 15 Perturbation testing of real and ideal single-circuit ACS Fig. 16 Testing of disturbance of ideal and real ACS with disturbance compensation. Parameter Processing the task Processing the disturbance of a single-circuit ACS without disturbance compensation Processing the disturbance of a single-circuit ACS with disturbance compensation ideal real ideal real ideal real Maximum overshoot 13,112,831313131 Regulation time, min 16937024047995327 Degree of attenuation 0,870,920,890,910,990,9 9 The ideal and real systems practically do not differ in maximum emission and degree of attenuation, but the real system has a significantly lower performance. It was experimentally found that the main influence on the performance is the backlash of the actuator. Therefore, when choosing automation equipment, special attention should be paid to the choice of actuator. 5. Calculation of the regulatory body and selection of automation equipment
5.1 Regulatory body calculation
P1=P2=2kgf/cm2 Fmax=115000kg/hour = 160 m3/hour Din=0.3m Determination of the total pressure drop in the network: Let's calculate the value of the Reynolds criterion at maximum flow: Condition for hydraulic smoothness of pipes: the condition is met, therefore the pipe is not hydraulically smooth. We determine the friction coefficient λ=0.0185 based on the value of the Re criterion and the ratio of the internal diameter of the pipe to the height of the pipeline roughness protrusions according to the nomogram. Find the total length of straight sections of the pipeline: Determination of the average speed in the pipeline at maximum flow: Let's calculate the pressure loss in straight sections of the pipeline: Let us determine the total coefficient of local resistance of the pipeline: Let's calculate the pressure loss in the local resistance of the pipeline: Total line pressure loss: Pressure drop in the control body at maximum flow: Let's find the maximum capacity of the regulatory body: Table of conditional capacity of regulatory authorities We select a regulatory body with a conditional throughput and a nominal diameter. Let's check the effect of viscosity on the throughput of the regulator; to do this, we will recalculate the value of the Reynolds criterion in accordance with the diameter of the nominal diameter of the regulator: We select this regulatory body without determining the correction factor for liquid viscosity. Let us determine the adjusted value of the maximum flow rate: Let's determine the relative values of expenses: Determination of the range of movement for n=0 with linear characteristic We determine the range of movements for: a) With linear characteristic: b) With equal percentage characteristic: 0.23< S < 0,57 We determine the maximum and minimum values of the transmission coefficient for the operating load range: a) For linear throughput characteristic: b) For equal percentage throughput: The value of the ratio of the minimum and maximum values of the transmission coefficient with a linear throughput characteristic is greater than with an equal percentage. Therefore, we choose a linear flow characteristic. Static imbalance of the shutter: Maximum possible pressure on the valve; Difference in area of the upper lower body; Medium pressure force on the rod: Rod diameter; Maximum pressure behind the valve 5.2 Selection of technical automation equipment
Small-sized control valve manufactured by LG Avtomatika. The pneumatic actuator is supplied complete with the valve. Nominal pressure Ru, MPa1.6 Nominal bore, mm200 Flow characteristics linear Temperature range of the controlled medium - 40. +500 Ambient temperature range -50…+70 Initial positions of the valve plunger NZ - normally closed Housing material 12Х18Н10ТThrottle pair material 12Х18Н10ТLeakage class for control valves according to GOST 23866-87 (according to DIN) VLeakage class according to GOST 9544-93В Isolating barrier spark-proof meter 631 isobar Basic barrier error when transmitting an analog signal: 0.05% Power input current limitation: 200mA Sensor side input current limitation: 23.30mA Supply voltage, V: 20.30 Explosion protection marking: ExiaIIC Response time, ms: 50 MTBF, hours: 50000 Thermal converter with a unified output signal THAU Metran 271 Output signal: 4.20mA Temperature range: - 40…800 O WITH Basic error limit: 0.25% Signal dependence on temperature: linear Vibration resistance: V1 Explosion protection marking: ExiaIICT5 Supply voltage, V: 14.34 Rosemount 8800D Vortex Flowmeter Output signal: 4.20mA with digital signal based on HART protocol, frequency pulse 0.10kHz, digital FF Medium temperature range: - 40…427 O WITH Volume flow measurement limit m 3/h: 27…885 Limit of permissible basic error: 0.65% Degree of protection against dust and water: IP65 Vibration resistance: V1 Explosion protection marking: ExiaIICT6 Maximum input supply voltage: 30V Maximum input current: 300mA 6. Metrological calculation of measuring channels
The block diagram of the temperature and flow measurement channels is as follows: Fig. 17 Block diagram of measuring channels. The error of this measuring system consists of the errors introduced by the sensitive element of the temperature sensor, the normalizing converter, the spark protection barrier, the communication line, and the input board of the microprocessor complex. At the moment, manufacturers of cables and data transfer interfaces have practically reduced the error introduced by the communication line to zero, therefore, it is not taken into account in calculations. In turn, the errors of the normalizing converter, the sensitive element, as well as the input/output board of the microprocessor complex are determined by the manufacturer, then the permissible error limit of the measuring channel will be determined as: γ dt=0.25% - thermal converter error; γ business=0.05% - error introduced by the spark protection barrier; γ PM=0% - error introduced by the communication line; γ IV γ dt=0.65% - thermal converter error; γ business=0.05% - error introduced by the spark protection barrier; γ PM=0% - error introduced by the communication line; γ IV=0.1% - I/O board error. This error will ensure the required channel measurement accuracy. 7. Calculation of the reliability of the automatic control system
The reliability of a control system is understood as the ability of the system to fulfill the requirements placed on it within a given time within the limits specified by its technical characteristics. It is impossible to completely eliminate equipment failure; therefore, the reliability of the control system cannot be 100%. Let's calculate the probability of sudden failures of the measuring channel if it is known that: for ExperionC300 controllers the mean time between failures tWed n =
150,000 hours; for thermal converter THAU Metran 271 MTBF tWed n=20000 hours; for Rosemount 8800D flowmeter MTBF tWed n=50000 hours; for spark protection barriers Metran 631 MTBF tWed n=50000 hours; for connecting wires, the probability of failure in 2000 hours is 0.004. Let us conditionally assume that the failure distribution law is exponential, then the probability of failure-free operation is determined by the formula: , where λ
=1/tWed n. Probability of failure-free operation of the ExperionC300 controller: Probability of failure-free operation of the thermal converter THAU Metran 271: Probability of failure-free operation of the Metran 631 spark protection barrier: Rosemount 8800D Flow Meter Probability: Probability of failure-free operation of communication lines:
Chapter 7. OPERATION OF AUTOMATION SYSTEMS
7.1. TASKS AND STRUCTURE OF THE AUTOMATION SYSTEMS OPERATION SERVICE AT THE ENTERPRISE
The main task in the operation of instruments and automation equipment is to ensure reliable and correct operation of individual units and the entire complex of these devices. The problem is solved through continuous monitoring, creation of normal operating conditions and timely elimination of all emerging defects, for which the enterprise organizes an automation systems operation service.
Start-up, normal operation, shutdown and repair - these are the main stages of the operational cycle of both technological equipment and the instruments and automation equipment that service this equipment. At each of the listed stages, the operation service performs work to ensure reliable and correct functioning of the automation system.
In the 70s, the Regulations on the instrumentation and automation service at food industry enterprises, developed by the NPO Pishcheprom-Avtomatika, were in force. In connection with the introduction of the USSR metrological service in our country, which consists of state and departmental metrological services, a departmental metrological service is organized at each enterprise. Therefore, this provision was replaced by a new Standard Regulation on the metrological service of a food industry enterprise, in accordance with which a metrological service is organized at each food enterprise.
The structure of the metrological service (MS) of a food enterprise determines the units included in its composition, the distribution of functions between units, their subordination and interrelation. The structure of MS is developed taking into account the structure and characteristics of the functioning of the enterprise (its subordination, category, number and relationships of production, seasonality of their work, number of shifts in workshops), equipment and characteristics of the functioning of the service (scope of work, quantitative and qualitative composition of measuring and automation equipment, availability material and technical base, condition and location of service premises, availability and qualifications of personnel, the possibility of cooperation in repairs, etc.), as well as prospects for the development of the service
For the next 3-5 years.
At enterprises of the 1st-3rd categories, MS is organized in the form of a laboratory, at enterprises of the 4th-6th categories - in the form of a laboratory or group. The category of an enterprise depends on the volume of production and the complexity of obtaining products. The metrological service is headed by the chief metrologist of the enterprise, who reports to the chief
Enterprise engineer.
The construction of MS is based on the following structural chain:
Link (group) - brigade. The laboratory at enterprises of the 1st-3rd categories includes six units: metrological support of production; maintenance of automation systems, measuring and automation equipment (MIA); SIA repair; development and implementation of production automation systems; verification of measuring instruments; accounting, storage and issuance of SIA. The first three links are also part of the laboratory (group), which is organized at enterprises of the 3rd to 6th categories.
SIA maintenance and repair units usually consist of special and general purpose teams. The level of specialization of personnel in a service group or team should ensure the possibility of interchangeability within two or three service areas. Depending on the nomenclature, quantity and complexity of the automated information equipment, the repair link is organized from teams with assignment to them of the repair of one or several types of automatic equipment: pyrometric and thermotechnical; pressure, vacuum and flow; electronic and pneumatic;
Masses and precision mechanics; quantity and composition of substances containing mercury; radioactive and ionizing radiation; electrical and electromechanical; actuators and
Mechanical devices.
At the head (base) enterprise of a plant, industrial or agro-industrial association, a central MS (laboratory) can be organized, which, along with six units of the metrological service of an enterprise of the 1st-3rd categories, may also contain units of coordination and planning, installation and adjustment, supply and configuration, and etc. In this case, technical service units are created at the remaining enterprises (productions) of the association. Metrologists heading the MS of these enterprises report to the chief metrologist of the association (plant, base enterprise).
If there is a small number of SIA at the enterprise, in agreement with the base organization at enterprises of the 4th-6th categories, it is allowed to organize a group of metrological support and maintenance as part of the service of the chief mechanic or power engineer, who in this case performs the duties of the chief metrologist of the enterprise. The MS group is headed by the group leader - senior engineer. The leadership of the group performing maintenance and repair is permitted by a senior foreman or foreman. Specialists working in these positions carry out administrative and technical management of the teams. The deputy chief metrologist is usually the head of one of the most important units.
The number and composition of the MS is determined by calculation, taking into account the number and nomenclature of the forces, types and volumes of work performed, the category of the enterprise, the operating conditions of the automation system and the MS, operating conditions of production (shift and seasonality), the level of labor organization and the established structure of the MS. Turnout number of service personnel
Where T I is the time spent on performing a specific i-th type of work; A I, - the average number of shifts in a calendar year for service personnel performing the 1st type of work (for single-shift work such as repairs, verification, etc., A I, = 1); k I , is a coefficient that takes into account the operating conditions of the automated testing equipment and the frequency of work; (SD - coefficient taking into account various additions and restrictions; F N - nominal working time during the year (F N = 2050...2100 hours); fee - coefficient of the payroll staff of the service (k C = 0,8...0,9).
When determining the number of employees by job category, calculations are made separately for each category.
A group and brigade are usually organized with at least five people and include workers of the following professions: repairman; mechanic; duty mechanic; automation and power systems adjuster; installer of electromechanical, radio engineering systems and automated information systems; laboratory assistant; laboratory assistant for electromechanical testing and measurements; tester of measuring instruments;
Tester of electrical machines and devices, etc. If the enterprise has an automated control system, the metrological service is included as independent links in this service. Such a division of the enterprise is usually headed by the deputy chief engineer of the enterprise or the head of the service, who simultaneously performs the duties of the chief metrologist.
Structurally, the automated control system service consists of those units that are part of the metrological service of the enterprise and the automated control system laboratory. The main functions of the latter are related to the operation of the computer center (CC) and its external devices (the structure of the ACS service is discussed in detail in paragraph 3.1).
7.2. METROLOGICAL SUPPORT
Metrological support is a complex of scientific and technical foundations and organizational measures that ensure the unity and required accuracy of measurements. The scientific and technical foundations of the Ministry of Defense include metrology as the science of measurements, methods and means of ensuring the uniformity of measurements and the necessary accuracy, and the standards of the State System for Ensuring the Uniformity of Measurements (GSI) as a set of interconnected rules, regulations, requirements and norms established by standards that determine the organization and methodology of work. on assessment and provision
Measurement accuracy.
The GSI includes two types of regulatory documents: basic standards, including GOST "Units of Physical Quantities", and standards of four other groups - state standards, methods and means of verification of measures and measuring instruments, standards of measurement accuracy and measurement techniques (MVI). These also include standard test programs.
The organizational basis of the Moscow Region is the metrological service of the USSR, which, in accordance with GOST 1.25-76, consists of state and departmental metrological services. The State Metrological Service (SMS), headed by the USSR State Standard, includes the following divisions:
The main center of the HMS (All-Union Scientific Research Institute of Metrological Service - VNIIMS), which carries out scientific and methodological management of the country's metrological service and the state standard data service;
Main centers and centers of state standards (research institutes in Moscow, Kharkov, Sverdlovsk, etc. and their branches), which carry out research and other work to improve metrological support in
Country; territorial bodies of Gosstandart in the union republics,
Headed by the republican departments of the State Standard of the USSR and including the republican centers of metrology and standardization;
Republican, interregional, regional and interdistrict laboratories for state supervision (LGN) of standards and measurement
Equipment, as well as their departments.
Along with those listed, the State Migration Service also includes the State Standard Reference Data Service, headed by the Main Reference Data Center, the State Standard Reference Data Service, headed by the Main Standard Reference Data Center, the State Time and Frequency Service of the USSR, the All-Union Association "Etalon", which unites factories, which manufacture and
Repairing exemplary measuring instruments.
The main activities of the State Migration Service are the creation and continuous improvement of the state system of unit standards; ensuring continuous improvement of the measuring instruments used in the country; transfer of the sizes of units of physical quantities to all measuring instruments used in the national economy;
State supervision over the state and correct application of measuring instruments at enterprises and organizations; standardization of measurement techniques.
The departmental metrological service, headed by the chief metrologist of the ministry or department, consists of a division of the ministry or department that manages the service; the head organization of the service, which methodically, scientifically, technically and in an organized manner manages the work of the basic organizations of the metrological service (MS) and MS of enterprises; base organizations of departmental MS, which provide scientific, technical, organizational and methodological guidance on metrological support (MS) of production of the product groups or types of activities assigned to them, as well as on the MS of attached enterprises or organizations; metrological services of enterprises or organizations.
Metrological support for production is aimed at obtaining high-quality and reliable information through measurement. Deficiencies in production engineering lead to erroneous conclusions and significantly increase defects; Increasing the level of MO production makes it possible to improve the quality and economic indicators of manufactured products.
The main tasks of the MO level of the metrological service of a food enterprise are: coordination and implementation of methodological management of work aimed at ensuring the unity and required accuracy of measurements in all departments of the enterprise;
Systematic analysis of the state of measurements, development and implementation of measures to improve the enterprise's MO, including proposals for the purpose of SIA and measurement techniques for managing technological processes, monitoring raw materials and testing products; introduction of normative and technical documentation (NTD) regulating measurement accuracy standards, metrological characteristics of automated measuring instruments, measurement techniques, methods and means of verification and other requirements for metrological support for production preparation; development of technical specifications for the design and manufacture of non-standard automated measuring instruments, auxiliary equipment, stands, devices for carrying out the necessary measurements, testing and control; organization and participation in the metrological examination of regulatory, technical, design, design and technological documentation, including those developed at the enterprise; participation in the analysis of the causes of violation of technological regimes, defective products, unproductive consumption of raw materials, materials and other losses associated with the state of the automated information technology; advanced training of the enterprise's MS employees and training for the enterprise's MS.
The MO link also communicates with the bodies of the State Standards Committee of the USSR when they carry out state supervision over the MO of preparation of production and testing of products, the condition, use, repair and verification of automated information systems at the enterprise, and other activities of the enterprise's MS. To the territorial bodies of the State Supervision of the USSR and the basic organization of the metrological service (BOMS) of the industry, the MO link provides information on the status of plans for the introduction of new "methods and SIA, which, after development and agreement with the base organization, are approved by the management of the enterprise. Standards and other scientific and technical documentation of the enterprise are also agreed upon with the BOMS. MO The metrological support unit also participates in the development and implementation of tasks provided for by the complex programs of the industry's MO, and develops proposals for draft annual and long-term plans for the industry's MO.
Planning of MS activities, carried out by the MO link, is regulated by the methodological instructions of VNIIMS and is carried out taking into account the production capacity of the enterprise, the range of products and technical capabilities. These plans include work aimed at ensuring plans state and industry standardization and metrological support for the activities of enterprise divisions; development or revision of enterprise standards (STP), verification schemes, measurement techniques, as well as tasks for the implementation of STO, GOSTs and OSTs.
Metrological examination is, as follows from the above list of tasks of the Ministry of Defense, part of the general complex of works on metrological support of production. Metrological expertise (ME) includes analysis and evaluation of technical solutions for selecting parameters to be measured, establishing accuracy standards and providing measurement methods and instruments.
Sections of documents that reflect requirements for established accuracy standards or contain information about measurement tools and methods are subject to metrological examination. During the metrological examination of technical documentation, which solves the problem of choosing measuring instruments - technological regulations, maps of technological processes with control operations, functional and schematic diagrams of devices with measuring instruments, the correctness of the choice of a measuring instrument or device is assessed.
During the metrological examination of technical documentation, which defines the parameters, properties or characteristics of machines, materials or processes, it is first identified which elements, parameters or properties are subject to control when their manufacturing or operation, and then, by searching through variants of standard methods, determine the testability of the object. If it turns out that due to unreasonably narrow tolerance fields of the controlled parameters it is impossible to ensure control using standard instruments, it is necessary first of all to analyze the possibility of expanding the tolerance fields.
Of particular importance is the ME of the production process, during which the compliance of the technological process with the requirements of design, technological and other normative and technical documentation for metrological support is established. One of the main documents that the ME at an enterprise must pass is the technological regulations for the production of products.
7.3. VERIFICATION WORKS
Verification of measuring instruments, like other metrological control activities, is the task of the MS verification unit of a food enterprise. Verification is designed to ensure the uniformity and reliability of measurements in the country and contributes to the continuous improvement of measuring instruments.
Measuring instruments, like any other automation equipment, are subject to wear and aging over time, even if all requirements for their operation and storage are strictly observed. Wear and aging are the main reasons for the gradual change in the metrological characteristics of measuring instruments, therefore it is necessary to systematically check them so that deviations in readings do not go beyond the permissible limits.
Verification of measuring instruments(SI) is the determination by a metrological body of errors and the establishment of its suitability for use. During the verification process, the size of units of physical quantities is transferred from the standard to the working SI. In the general case, transferring the size of units is finding the metrological characteristics of a verified or certified SI using a more accurate SI. Schemes for such transmission include standards, model and working measuring instruments (Fig. 7.1).
Primary standard - This is the standard of the highest accuracy currently achievable, officially approved as the state primary standard. There can only be one in one country. Working standards (their number is not limited) are intended to convey the dimensions of physical quantities to exemplary first-class SIs and the most accurate working SIs. In order to relieve the primary standard from the work of transferring the sizes of units of physical quantities and reduce its wear, a copy standard is created, which is a secondary standard and is intended to transfer the sizes of physical quantities to the working standard. Model SIs are also intended to convey the sizes of physical quantities and are divided into digits (there can be a maximum of five), and the number of the digit means the number of steps in transmitting the size of a unit to a given model SI. Reducing the number of digits reduces the error in transmitting the size of units, but also reduces verification productivity. Working SI are used only
Rice. 7.1. Scheme for transferring unit sizes from the standard to working measuring instruments
For measurements not related to the transfer of sizes of units of physical quantities, and, as can be seen from Fig. 7.1 are also divided into five classes.
To determine the reliable error of a working SI, it is sufficient that the error of the reference instrument be 10 times less than the error of the working SI. Due to difficulties in implementing such a ratio, ratios of 1:3, 1:4, 1:5 are usually used; as an exception, a ratio of 1:2 is allowed.
The main source document for organizing the verification of specific working measuring instruments is the verification scheme. Verification schemes can be all-Union and local. All-Union verification schemes are developed by metrological institutes and approved by the USSR State Standard. They are the basis for the development of local verification schemes, state standards and methodologies for methods and means of verification of standard and working measuring instruments. Local verification schemes are developed, if necessary, and implemented by the MS verification unit. They are coordinated with the territorial bodies of Gosstandart, which perform verification of the original standard measuring instruments included in the local verification scheme. The latter covers exemplary and all working measuring instruments of a given physical quantity that are in operation at the enterprise or put into circulation by industry, as well as methods for their verification. The drawing of the verification scheme, carried out in accordance with GOST 8.061-73, indicates the name of the measuring instrument, ranges of values of physical quantities, designations and error estimates, and the name of the verification method.
The most common verification methods are:
Direct comparison, which consists in comparing the testimony of the verified and standard measuring instruments;
Comparison - in comparison of SI with a standard one using a comparison measuring device (comparator);
According to exemplary measures - in measuring the value of a physical quantity that is reproduced by an exemplary measure or at the same time compared with the value of an exemplary measure.
Based on the time of carrying out, there are primary, periodic, extraordinary and inspection verifications. Primary verification is carried out when measuring instruments are released from production or repair, periodic verification is carried out during operation at established verification intervals. Extraordinary verification is carried out regardless of the timing of periodic verification in cases where it is necessary to verify the serviceability of measuring instruments or before putting imported measuring instruments into operation. The need for extraordinary verifications also arises when monitoring the results of periodic verification or carrying out work to adjust the verification intervals, in case of damage to the verification mark, seal and loss of documents confirming the verification.
Extraordinary verification is also carried out during commissioning of measuring instruments after storage, during which there was no periodic verification, or during installation their as components after the expiration of half of the warranty period for them specified by the supplier in the accompanying documentation. Inspection verification accompanies the metrological audit of measuring instruments of enterprises that repair, operate, store and sell these instruments.
Depending on the purpose of the measuring instruments being verified, verification can be state or departmental. Of the measuring instruments used at food industry enterprises, the following measuring instruments are subject to mandatory state verification:
Used as initial standard measuring instruments (MI) in departmental metrological services; owned by enterprises and used as standard measuring instruments by the state metrological service; produced by equipment repair enterprises after repairs performed for other enterprises; intended for use as working instruments for measurements related to the accounting of material assets, mutual settlements and trade, protection of workers' health, ensuring labor safety and health in accordance with the list approved by the State Standard of the USSR. The remaining working measuring instruments used at food industry enterprises are subject to departmental verification.
In accordance with the nomenclature list approved by the State Standard of the USSR, in particular, flow meters for liquids, steam and gas with secondary devices, industrial gas, water and heat meters, meters for oil, petroleum products, alcohol and other industrial liquids and food products are subject to mandatory state verification , dispensers for liquid food products, mass measuring instruments and devices, line length measures, industrial meters of three-phase current electrical energy, refractometers, saccharimeters, photoelectrocolorimeters and density meters used for settlements with consumers.
State verification of instruments is carried out by metrologists-verifiers of the state metrological service. In the presence of the necessary premises, all regulatory documents, model measuring instruments that have passed state verification, as well as metrologists-verifiers, the USSR State Standards bodies issue registration certificates to departmental metrological services for the right to carry out verification, which can be combined with certificates for the right to manufacture and repair measuring instruments . Verification metrologists undergo special training and pass exams at the state metrological service.
If the MS verification unit of a food enterprise does not have the right to conduct departmental verification of certain measuring instruments, then the latter are verified in the basic bodies of the departmental MS industry or in the bodies of the state metrological service. The verification of measuring instruments of enterprises is carried out by the USSR State Standards bodies in stationary or mobile laboratories, as well as directly at enterprises by seconded state verifiers.
Measuring and automation equipment subject to verification is verified according to state or departmental verification schedules drawn up by the MS verification unit of the enterprise, agreed upon with the local government supervision authority and approved by the chief engineer of the enterprise. Typically, verification schedules are drawn up for instruments and automation equipment by type of measurement.
The frequency of verification of measuring instruments is established in accordance with the methodological instructions of the USSR State Standard for determining the inter-verification interval of working measuring instruments, taking into account the actual stability of readings, operating conditions and the degree of workload of measuring instruments. The frequency of verification of measuring instruments owned by the enterprise and subject to departmental verification must be agreed upon with the base organization. Measuring instruments at food industry enterprises undergo departmental verification, as a rule, once a year. The exceptions are potentiometers and bridges, ammeters and voltmeters, milliammeters, millivoltmeters, wattmeters and phase meters, which are checked every 6 months.
For measuring instruments in storage, the verification intervals are determined equal to double the verification intervals of similar measuring instruments in operation. An exception is made for measuring instruments received for storage after their release, for which the calibration interval should not exceed the manufacturer’s warranty period, and measuring instruments that are stored in conditions that ensure their serviceability, and which are checked only before use.
Measuring instruments are verified in accordance with state standards for methods and means of verification or according to the instructions of the USSR State Standard and the methodological instructions of its metrological institutes. In the absence of the specified regulatory documents, developers of the relevant measuring instruments must draw up guidelines or instructions for their verification, which are approved by the head of the departmental metrological service of the enterprise using these measuring instruments, or the head of a higher departmental metrological organization.
During the verification process, a protocol is kept where the results and the conclusion about the suitability of the measuring instruments for use are recorded. A suitable device is sealed or a verification stamp is placed on it. The suitability of the device for operation during the verification interval can also be certified by a certificate or other technical document. A note on the verification of devices indicating the date and its results is made in the device passport or other document replacing the passport. Passports for measuring instruments are issued by the MS accounting group of the enterprise at the request of the technical maintenance department of the enterprise. The passport contains detailed technical characteristics of the device, information on verification, operation and repair.
Some food industry enterprises use non-serial production measuring instruments, imported ones, or serially produced measuring instruments with modifications, as a result of which their metrological characteristics do not meet the requirements of regulatory and technical documentation. For such measuring instruments, the MS verification group of the enterprise carries out metrological certification, during which the nomenclature of metrological characteristics to be determined is established;
Numerical values of metrological characteristics; procedure for metrological maintenance of instruments during their operation (certification or verification). Based on the results of metrological certification, a protocol is drawn up in two copies, which are signed by the group leader and performers. If the outcome of metrological certification is positive, a certificate (certificate) is issued for each measuring instrument.
The MS verification group of a food enterprise, along with the listed functions, also performs a number of others:
ensures storage and comparison in the prescribed manner of working standards and standard samples of the composition and properties of substances and materials; maintains exemplary measuring instruments in proper condition and ensures their exploitation;
controls the condition and use of automated measuring instruments, product testing tools, the availability and correct application of measurement techniques and compliance with metrological rules in all departments of the enterprise;
carries out acceptance and certification of non-standardized information and information instruments entering the enterprise;
exercises control over the metrological support of all production activities of the enterprise's divisions, the implementation of plans for organizational and technical measures for the metrological support of their activities, and the introduction of new automated information systems into production.
7.4. MAINTENANCE
DEVICES AND AUTOMATION MEANS
The main tasks of maintenance are continuous monitoring of the operation of instruments and automation equipment and the creation of conditions that ensure their serviceability, performance and the necessary resource during operation. To perform these tasks, a unit (group) for technical maintenance of automation systems and automated information systems, consisting of shift teams, is created within the metrological service.
The MS shift team of a food enterprise includes mechanics on duty and a foreman (a foreman or a highly qualified worker of categories V-VI). MS shift personnel are part of the technological workshop shift and therefore have double subordination. Administratively and technically, he is subordinate to the chief metrologist, and operationally to the shift supervisor (duty engineer) of the technological workshop. Operational subordination means that shift personnel perform work on the instructions or with the knowledge of the shift supervisor.
Maintenance work on automation systems includes drawing up maintenance schedules and their implementation, as well as unscheduled maintenance, primarily associated with prompt repairs or replacement of failed powertrains; implementation of operational control over the condition and functioning of automation systems and automated information systems, ensuring their proper technical condition, including current repairs of the automated testing equipment and pipe routes, removal and installation of automatic testing equipment for repair and verification; control over the correct operation and rational use of automation systems and compliance with current operating rules.
Operational monitoring of the condition and functioning of automation systems consists of systematic shift-by-shift or daily monitoring of the operation of automated information systems installed both at control points and in production premises, in order to identify emerging malfunctions and prevent their development. These works are carried out by visual observation of the condition of the SIA. During such inspections, violations of the seals of connecting pipe lines and fittings are identified and eliminated, the instruments are inspected and cleaned, the chart of the recording device is checked for correct installation in terms of time and the value of the controlled variable, as well as the presence of the necessary records on the chart (instrument positions and recording dates), the chart is replaced , refill recorder pens with ink, check the operation of switches, the presence of power and lubrication, and monitor the operation of automatic regulators.
When changing charts and rolls of recorders for devices that have an integrator, the time of their replacement and the readings of the integrator are indicated on the chart or roll, and first of all, the charts and rolls of devices are changed, according to the readings of which payments are made for the raw materials or energy used. Monitoring the operation of automatic regulators is carried out by comparing the nature of the change in the regulated variable with the readings and records of instruments that monitor the quantities associated with the regulated variable.
Maintenance (MA) of automation systems and automated information systems, carried out in accordance with the maintenance schedule, which is approved by the chief engineer of the enterprise, includes the following operations:
External inspection, cleaning of dust and residues of technological products, checking the serviceability of communication lines and the integrity of seals;
Checking performance at control points, identifying and eliminating minor defects that arose during operation;
Replacing diagrams, cleaning recorders and refilling them with ink, lubricating movement mechanisms, adding or changing special fluids, eliminating their leaks;
Checking the operation of the automation system in case of detection of discrepancies during the process and the readings of measuring instruments;
Washing measuring chambers, filling differential pressure gauges with mercury, correcting seals and fasteners, checking select pressure and flow devices, etc.;
Drying SIA elements and cleaning contacts;
checking refrigerators, filters, water-jet pumps, power supplies, indicating and recording units of measuring instruments for the composition and properties of substances;
cleaning, lubricating and checking relays, sensors and regulator actuators;
checking the density of impulse and connecting lines, replacing faulty individual elements and assemblies;
checking the presence of power in control and signaling circuits, testing sound and light alarms;
checking the operation of circuits and the correctness of tasks for their operation;
inspection of automation panels, interlocking devices, alarm and protection equipment.
The maintenance frequency is on average once every
I-2 months For liquid and gas quantity meters, pipe differential pressure gauges, hydraulic vacuum, pressure and flow regulators with a membrane measuring device, hydraulic actuators, set point for electronic control devices, electrical measuring instruments and relay equipment, the maintenance frequency can be increased to 6 months, and for air reducers , pneumatic remote control panels, control valves with pneumatic diaphragm or electric motor drive, electric actuators, direct-acting gas or fuel oil pressure regulators, pneumatic control units, induction flow meters, thermocouples and resistance thermometers - up to 3 months. Converters of pH meters and mass measuring devices are subject to maintenance once every 10 days. In rooms where the temperature exceeds 30 °C for a long time, the frequency of scheduled work is reduced by 2 times, in dusty rooms (process dust penetrates into the equipment) - by 3 times, in rooms with a chemically active environment (relative to insulation and other parts of the equipment) - 4 times.
In accordance with the schedules of planned preventive maintenance (PPR), shift personnel also replace devices sent for repair. The procedure for carrying out planned work during a shift is regulated by the job descriptions of MS shift personnel.
The maintenance link, along with technical maintenance and operational control, is involved in examining the causes of accidents due to failures of automation systems and automated information systems and developing measures to their elimination; organizes and trains production personnel in the rules of technical operation of automation systems and automated information systems; controls the quality of installation and commissioning work and their compliance with technical documentation when performing these works by specialized organizations; participates in testing and acceptance into operation of newly installed and adjusted automation systems from installation and commissioning organizations; carries out adjustment work before the launch of seasonal production and when introducing new and improving existing automation and power systems; improves the organization of maintenance of automation systems.
During the shift, an operational log of the duty personnel is kept, which records all cases of failure of instruments and automation equipment, regardless of the reasons. their occurrences, measures taken to eliminate failures, operational switching, replacement of instruments and automation equipment, technical inspections and other work performed by duty personnel. The delivery and acceptance of shifts are documented with the signatures of senior duty officers in the operational log. The person handing over the shift must draw the attention of the person receiving the shift to the “bottlenecks” of the automation system.
Shift personnel must have certain production skills and knowledge. Therefore, those on duty first undergo safety training and a knowledge test on the automation system of the technological facility that them to be serviced. The attendants must have a good knowledge of the technological diagram of the serviced production complex, the process of managing it, the layout plan of process equipment and pipelines, the purpose of each element of the automation system, the location of the primary receiving elements and regulatory bodies/instruments in place, their interrelation, the location and direction of the routes.
To carry out the entire range of preventive work, operating areas are equipped with portable laboratory instruments (potentiometers, bridges, resistance stores, control pressure gauges, voltammeters, mercury thermometers, megohmmeters, voltage indicators), tools (set of plumbing tools, electric drill, soldering irons, portable lamp) and materials ( ink and chart paper, wires and insulating tape, fasteners, dry galvanic cells, cleaning material, lubricating oils, gasoline, kerosene, alcohol).
To carry out maintenance, mechanics on duty additionally receive special devices and instruments for checking individual components and parts of automatic control and regulation devices. In addition, the operation area must have backup instruments and automation equipment to replace those sent for repairs in accordance with maintenance schedules and those that fail as a result of unscheduled failures. The group for recording, storing and issuing SIA closely interacts with this division of MS, which creates an exchange and rental fund for SIA, maintains their technical records, etc.
SYSTEMS AND COMPUTING EQUIPMENT
Computer maintenance includes a set of organizational and technical measures carried out in order to ensure the required reliability parameters. It can be individual and centralized. In the first case, the shift staff servicing the computer is staffed taking into account the considerations given in clause 7.1. With centralized maintenance, maintenance is carried out by special centers under contracts concluded with enterprises.
When servicing systems and computer equipment, a distinction is also made between scheduled and unscheduled work. Planned work is carried out in accordance with the schedule of planned preventive work (PPR), which determines the frequency, regulations and type of work. For example, for the EC-1030 machine, the following regulations and frequency of maintenance (in hours) are recommended: daily inspection 1, two-weekly 4, monthly 8 and semi-annually 72.
Daily maintenance usually includes inspecting devices, running a quick check test their performance, as well as cleaning, lubrication, adjustment and other work provided for in the operating instructions for external devices. Every two weeks, diagnostic tests are run, as well as all types of two-week preventive maintenance provided for in the instructions for external devices. The functioning of the machine’s technical equipment, included in its software, is checked monthly at rated voltage values and preventive changes thereof by ± 5 %. Unusable standard elements are replaced with serviceable ones. The same work is carried out during six-month prophylaxis. During monthly and semi-annual maintenance, the corresponding preventive work provided for in the operating instructions for external devices is also carried out.
Only specialists who have passed exams on computer devices, circuit documentation and technical descriptions, have studied the operating instructions and have received a certificate of authorization are allowed to perform computer maintenance work. their operation. To carry out the entire range of preventive maintenance, maintenance personnel are provided with fault diagnostic tools, spare tools, instruments, parts, etc. (spare parts), service equipment for checking external devices, replaceable functional units and power supplies. The service equipment includes stands for testing power supplies, logical and special standard elements, and cells of external devices.
The main operational documents of a computer are the form, the operating instructions for the computer and devices, the operating manuals for diagnostic and functional tests, diagnostic reference books and the computer operation log.
7.5. REPAIR WORK
DEVICES AND MEANS AUTOMATION
Repair work is carried out in order to eliminate defects that have caused changes in the technical characteristics of devices and automation equipment. For measuring instruments, these are, first of all, metrological characteristics, as well as the appearance of the device (the condition of the reading device, the housing and its elements, connecting and auxiliary devices). The requirements for the technical characteristics of devices and automation equipment are regulated by regulatory and technical documentation.
Repair of instruments and automation equipment at a food enterprise is carried out by a repair group of the metrological service. If there are no departments in this group that carry out repairs of some measuring instruments, the repair of the latter is carried out in special instrument repair organizations that have a registration certificate from the USSR State Standards Authority for the right to repair measuring instruments.
There are planned repairs, which are carried out according to PPR schedules, and unscheduled ones. The need to carry out the first is due to the constant change in the characteristics of instruments and automation equipment as a result of wear and aging. Wear is associated primarily with changes in the state of rubbing surfaces and dimensions of products, contamination of kinematics units at joints, electrochemical processes occurring under the influence of electric current, etc. However, even when not in operation, instruments and automation equipment are subject to aging associated with irreversible physical effects. chemical changes.
The rate of wear and aging processes depends primarily on the operating conditions of devices and automation equipment: ambient temperature and humidity, dust, the presence of aggressive vapors and gases, the action of magnetic and electric fields, vibration and various radiations. Under constant operating conditions, the influence of all of these factors can be assessed from the point of view of determining the planned overhaul intervals that ensure the operation of devices and automation equipment subject to the normal performance of specified functions.
Premature failure of instruments and automation equipment occurs as a result of device overload due to its improper activation or careless handling. Such types of failures are detected either directly as a result of work or during periodic verification of measuring instruments. In this case, unscheduled repairs are necessary.
Planned repairs of instruments and automation equipment are most often carried out during the period of repair of process equipment after the end of the food processing season. It is advisable to carry out unscheduled repairs by replacing the repaired devices and automation equipment with backup devices.
Instruments and automation equipment sent for repair must be accompanied by passports, certificates or other technical documents confirming the verification (if any) and defective labels indicating the type of repair (scheduled or unscheduled). For unscheduled repairs, the label indicates the nature of the malfunction that caused the repair.
Depending on the nature of the device malfunction and the extent of damage, a distinction is made between current and major repairs. The first is usually carried out at the installation site of the device by repair personnel, but can also be carried out in a repair shop. Current repair is the minimum type of repair in terms of the volume of work performed, which ensures the normal operation of measuring and automation equipment (M&A). Along with SIA maintenance work, current repairs include the following work:
Partial disassembly and reassembly of measuring systems with replacement of individual unusable parts (rings, screws, arrows);
Partial disassembly and adjustment of moving systems, correction or replacement of damaged parts (springs, tubes, screws, fasteners), cleaning and lubrication of components;
Replacement of SIA elements that have exhausted their service life, elimination of minor breakdowns;
Checking the quality of insulation and condition of the measurement and power supply circuits of the automated measuring equipment;
Correction of seals, elimination of backlash in individual mechanisms, packing of oil seals, replacement of glass and scales;
Troubleshooting joints of moving parts.
At food enterprises, most automated equipment is subject to routine maintenance once every 6 months, and temperature measuring instruments and gas analyzers - once every 4 months. The inspection completes the current repair.
Overhaul of SIA is carried out in the MS repair shop or in a specialized organization. It affects devices that have significant wear on parts, as well as damage, and therefore require restoration of full or close to full service life with the replacement or repair of any parts or assemblies.
During a major overhaul, in addition to performing part of the work included in the current repair, the following work can also be carried out:
Installation and adjustment of new scales or dials;
Repair of the body with straightening of mounting surfaces;
Complete disassembly and reassembly of the measuring part and individual components, washing, repair or replacement of parts (thrust bearings, springs, suspensions, weights, etc.), repair of components or their complete replacement;
Disassembly and assembly of SI recording mechanisms, their revision, cleaning and replacement;
Checking the measuring circuit of the measuring instrument (MI), adjusting and adjusting the readings at control points, preparing the SI for delivery to the verifier.
Overhaul of measuring instruments at a food enterprise is usually carried out once every 12 months. The MS repair group also issues requests to the enterprise divisions for the manufacture and acquisition of parts, materials and spare parts for the repair of SIA.
WIRING AND EQUIPMENT
Repair of wiring and equipment includes dismantling, repair and installation of select devices and installation units of primary receiving elements built into process equipment, pipe wiring and cable lines, panels, consoles, etc. At a food enterprise, these works are performed by a technical service group, and in central MS - installation and adjustment group during the period of shutdown and repair of process equipment.
Stopping technological equipment can be emergency or planned. The first is usually short-term. Therefore, during this period, priority urgent work is performed that cannot be performed during normal operation of the installation. In this case, those components of automation systems whose serviceability was in doubt during the routine maintenance of devices and automation equipment are subject to inspection and verification. The results of emergency installation and repair work are recorded in the operational log of the duty personnel.
During a planned shutdown of a process unit, in accordance with current instructions and directions, the shift supervisor sequentially turns off instruments and automation equipment, which is noted in the operational log. Installation and repair work begins only after a complete shutdown of the process unit and disconnection of instruments and automation equipment. First, those devices and automation equipment, cable and pipe wiring are dismantled, which, due to their location near process equipment and pipelines, can be damaged during repairs.
Installation and repair work is carried out on the basis of a defective list, which indicates the order and timing of the work, and the general schedule for repair work. When drawing up a defective list, the comments of the operating personnel are taken into account.
During a planned shutdown, installation and repair work is carried out in the following sequence. First of all, they carry out work that cannot be performed on operating process equipment, which is associated with a violation of the tightness of process equipment and pipelines. These include repairs of sampling devices, regulators, restriction devices, pipe lines connected to sampling devices without shut-off valves, etc. Secondly, work is carried out, the implementation of which on existing equipment is associated with significant difficulties or danger, such as, for example , repair of connecting routes laid in hard-to-reach places with high ambient temperatures. In the third place, repair work is carried out on automation systems for which there is no operational reserve, and then all other installation and repair work. The results of planned installation and repair work are recorded in a defect report or special journals.
CHECK QUESTIONS for chapter 1
1. Name the types of technical documentation.
2. What main sections of the project do you know?
3. In what modes can the automated process control system operate?
4. How is local automation systems designed?
5. How is the design of automated control systems carried out?
To Chapter 2
1. What are block diagrams?
2. What problems are solved when designing block diagrams of management and control?
3. What is an automation scheme?
4. Name the tasks of designing automation circuits.
5. How is the selection of measuring instruments carried out?
6. How is the selection of control devices carried out?
7. What is the order of execution of automation schemes?
8. What is a circuit diagram?
9. What are the requirements for circuit diagrams?
10. What kind of management is called centralized?
11. What is the operating algorithm of the circuit?
12. Name the methods for developing a structural diagram.
13. What requirements must be taken into account when moving to a circuit diagram?
14. How should elements be depicted on electrical circuit diagrams?
15. Name the features of the development of fundamental pneumatic schemes
16. Name the tasks of designing power supply systems.
17. How is the implementation of electrical power supply circuit diagrams carried out?
18. How is the type and design of switchboards and consoles selected?
19. Name the methods for making connection diagrams for internal panel wiring.
20. What are the challenges when designing electrical wiring? pipe lines?
To Chapter 3
1. Name the types of ACS support.
2. What automated process control systems structures do you know?
3. Name the functions of the operational personnel of the automated process control system.
4. What is included in the project documentation for organizational support?
5. What subsystems are included in the technical support?
6. What documents are included in the design documentation for technical support of automated process control systems?
7. What is the structure of the software?
8. Name the operating systems.
9. What applies to information support?
10. What is metrological support?
11. What features characterize technological complexes?
To Chapter 4
1. What types of software are typical for computer-aided design systems?
2. What caused the need to create CAD?
3. Name the levels of CAD.
4. Name the tasks of methodological support for CAD.
5. What main types of computer technology do you know?
6. What is an automated workstation?
7. Name the specific operators of the BASIC language,
8. How is information modified?
9. Name the principles of conservation in mathematics and software.
10. How are graphic operations implemented on a microcomputer?
11. Outline the methodology for using primitives when entering graphic information.
12. What is the layout of the equipment for boards and consoles?
13. What are the objectives of placement?
To Chapter 5
1. How are installation and commissioning work organized?
2. How are sampling devices and primary measuring transducers mounted?
3. How are instruments, regulators and actuators installed?
4. Name the stages of setting up local automation systems.
To Chapter 6
1. What is the organization of work during the installation and implementation of automated control systems?
2. Name the stages of work when installing an automated control system.
3. What is included in the installation project?
4. Name the stages of setting up technical equipment.
5. Name the types of debugging.
6. What methods do you know for detecting and localizing errors in software packages?
7. What is testing and what is it? types of it?
8. What does complex setup and debugging of the system consist of?
To chapter 7
1. Name the tasks of operating instruments and automation equipment.
2. What does metrological support include for the automation systems operation service?
3. What is verification of measuring instruments?
4. What is the purpose of the primary standard?
5. What are the maintenance tasks of the automation systems operation service?
6. State the purpose and means of repair work.
annotation
The purpose of this course project is to acquire practical skills in analyzing the technological process, selecting automatic control means, calculating measuring circuits of instruments and control means, as well as teaching the student independence in solving engineering and technical problems of constructing automatic control circuits for various technological parameters.
Introduction
Automation is the use of a set of tools that allow production processes to be carried out without the direct participation of a person, but under his control. Automation of production processes leads to increased output, reduced costs and improved product quality, reduces the number of service personnel, increases the reliability and durability of machines, saves materials, improves working conditions and safety precautions.
automation and monitoring of their action. If automation facilitates human physical labor, then automation aims to facilitate mental labor as well. The operation of automation equipment requires highly qualified technical personnel.
In this case, the production of thermal and electrical energy at any given time must correspond to consumption (load). Almost all operations at thermal power plants are mechanized, and transient processes in them develop relatively quickly. This explains the high development of automation in thermal energy.
Automating parameters provides significant benefits:
1) ensures a reduction in the number of working personnel, i.e. an increase in their labor productivity,
3) increases the accuracy of maintaining the parameters of the generated steam,
Automation of steam generators includes automatic regulation, remote control, technological protection, thermal control, technological interlocks and alarms.
Automatic regulation ensures the progress of continuously occurring processes in the steam generator (water supply, combustion, steam superheating, etc.)
Remote control allows the personnel on duty to start and stop the steam generator unit, as well as switch and regulate its mechanisms at a distance, from the console where the control devices are located.
flowing in a steam generator installation, or are connected to the measurement object by service personnel or an information computer. Thermal control devices are placed on panels and control panels, as convenient as possible for observation and maintenance.
eliminate incorrect operations when servicing a steam generator installation, ensure shutdown of equipment in the required sequence in the event of an accident.
emergency condition of the steam generator and its equipment. Sound and light alarms are used.
The operation of boilers must ensure reliable and efficient production of steam of the required parameters and safe working conditions for personnel. To meet these requirements, operation must be carried out in strict accordance with laws, rules, norms and guidelines, in particular, in accordance with the “Rules for the design and safe operation of steam boilers” of Gosgortekhnadzor, “Rules for the technical operation of power plants and networks”, “Rules for technical operation of heat-using installations and heating networks".
A steam boiler is a complex of units designed to produce water steam. This complex consists of a number of heat exchange devices interconnected and used to transfer heat from fuel combustion products to water and steam. The initial carrier of energy, the presence of which is necessary for the formation of steam from water, is fuel.
The main elements of the work process carried out in a boiler plant are:
1) fuel combustion process,
2) the process of heat exchange between combustion products or the burning fuel itself with water,
3) the process of vaporization, consisting of heating water, evaporating it and heating the resulting steam.
During operation, two flows interact with each other are formed in boiler units: the flow of the working fluid and the flow of the coolant formed in the furnace.
As a result of this interaction, steam of a given pressure and temperature is obtained at the output of the object.
One of the main tasks that arises during the operation of a boiler unit is to ensure equality between the energy produced and consumed. In turn, the processes of steam formation and energy transfer in the boiler unit are uniquely related to the amount of substance in the flows of the working fluid and coolant.
Fuel combustion is a continuous physical and chemical process. The chemical side of combustion is the process of oxidation of its combustible elements with oxygen. passing at a certain temperature and accompanied by the release of heat. The intensity of combustion, as well as the efficiency and stability of the fuel combustion process, depend on the method of supplying and distributing air between the fuel particles. Conventionally, the fuel combustion process is divided into three stages: ignition, combustion and afterburning. These stages generally occur sequentially in time and partially overlap one another.
Calculation of the combustion process usually comes down to determining the amount of air per m3 required for the combustion of a unit mass or volume of fuel, the amount and composition of the heat balance and determining the combustion temperature.
The meaning of heat transfer is the heat transfer of thermal energy released during fuel combustion to water, from which it is necessary to obtain steam, or steam, if it is necessary to increase its temperature above the saturation temperature. The heat exchange process in the boiler occurs through water-gas-tight heat-conducting walls called the heating surface. Heating surfaces are made in the form of pipes. Inside the pipes there is a continuous circulation of water, and outside they are washed by hot flue gases or receive thermal energy by radiation. Thus, all types of heat transfer take place in the boiler unit: thermal conductivity, convection and radiation. Accordingly, the heating surface is divided into convective and radiation. The amount of heat transferred through a unit heating area per unit time is called the thermal stress of the heating surface. The magnitude of the voltage is limited, firstly, by the properties of the heating surface material, and secondly, by the maximum possible intensity of heat transfer from the hot coolant to the surface, from the heating surface to the cold coolant.
The intensity of the heat transfer coefficient is higher, the higher the temperature difference of the coolants, the speed of their movement relative to the heating surface, and the higher the cleanliness of the surface.
lies in the fact that individual molecules of a liquid located at its surface and possessing high speeds, and therefore greater kinetic energy compared to other molecules, overcoming the force effects of neighboring molecules, creating surface tension, fly out into the surrounding space. With increasing temperature, the intensity of evaporation increases. The reverse process of vaporization is called condensation. The liquid formed during condensation is called condensate. It is used to cool metal surfaces in superheaters.
The steam generated in the boiler unit is divided into saturated and superheated. Saturated steam is in turn divided into dry and wet. Since thermal power plants require superheated steam, a superheater is installed to superheat it, in which the heat obtained from the combustion of fuel and waste gases is used to superheat the steam. The resulting superheated steam at temperature T=540 C and pressure P=100 atm. goes for technological needs.
The operating principle of a boiler plant is to transfer the heat generated during fuel combustion to water and steam. In accordance with this, the main elements of boiler installations are the boiler unit and the combustion device. The combustion device serves the fuel in the most economical way and converts the chemical energy of the fuel into heat. The boiler unit is a heat exchange device in which heat is transferred from the combustion products of the fuel to water and steam. Steam boilers produce saturated steam. However, during transportation over long distances and use for technological needs, as well as at thermal power plants, the steam must be superheated, since in a saturated state, upon cooling, it immediately begins to condense. The boiler includes: a firebox, a superheater, a water economizer, an air heater, lining, a frame with stairs and platforms, as well as fittings and fittings. Auxiliary equipment includes: draft and feed devices, water treatment equipment, fuel supply, as well as instrumentation and automation systems. The boiler installation also includes:
1. Tanks for collecting condensate.
2. Chemical water treatment plants.
3. Deaerators for removing air from chemically purified water.
4. Feed pumps for supplying feed water.
5. Installations for reducing gas pressure.
6. Fans for supplying air to the burners.
Smoke exhausters for removing flue gases from furnaces. Let's consider the process of producing steam with given parameters in a boiler house running on gas fuel. Gas from the gas distribution point enters the boiler furnace, where it burns, releasing an appropriate amount of heat. The air required for fuel combustion is forced by a blower fan into the air heater located in the last gas duct of the boiler. To improve the fuel combustion process and increase the efficiency of the boiler, the air can be preheated by flue gases and an air heater before being supplied to the firebox. The air heater, perceiving the heat of the exhaust gases and transferring it to the air, firstly, reduces heat loss with the exhaust gases, and secondly, improves the conditions of fuel combustion by supplying heated air to the boiler furnace. This increases the combustion temperature and the efficiency of the installation. Part of the heat in the firebox is transferred to the evaporative surface of the boiler - the screen covering the walls of the firebox. The flue gases, having given up part of their heat to the radiation heating surfaces located in the combustion chamber, enter the convective heating surface, are cooled and removed through the chimney into the atmosphere by a smoke exhauster. Water continuously circulating in the screen forms a steam-water mixture, which is discharged into the boiler drum. In the drum, steam is separated from water - the so-called saturated steam is obtained, which enters the main steam line. The flue gases leaving the furnace wash the coil economizer, in which the feed water is heated. Heating water in an economizer is advisable from the point of view of fuel economy. A steam boiler is a device that operates under difficult conditions - at high temperatures in the furnace and significant steam pressure. Violation of the normal operating mode of the boiler installation can cause an accident. Therefore, each boiler installation is equipped with a number of devices that issue a command to stop the supply of fuel to the boiler burners under the following conditions:
1. When the pressure in the boiler increases beyond the permissible limit;
2. When the water level in the boiler decreases;
3. When the pressure in the fuel supply line to the boiler burners decreases or increases;
4. When the air pressure in the burners decreases;
To control the equipment and monitor its operation, the boiler room is equipped with instrumentation and automation devices.
1. Reducing the pressure of gas coming from the hydraulic fracturing;
2. Reducing the vacuum in the boiler furnace;
3. Increasing the steam pressure in the boiler drum;
5. Extinguishing of the torch in the furnace.
3. Selection of means for measuring technological parameters and their comparative characteristics
3. 1 Selection and justification of control parameters
The choice of controlled parameters ensures obtaining the most complete measurement information about the technological process and the operation of the equipment. Temperature and pressure are subject to control.
4. Selection of monitoring and control parameters
The control system must ensure the achievement of the control goal due to the specified accuracy of technological regulations in any production conditions while observing the reliable and trouble-free operation of the equipment, explosion and fire hazard requirements.
The purpose of power consumption management is to: reduce specific electricity costs for production; rational use of electricity by technological services of departments; proper planning of electricity consumption; control of consumption and specific electricity consumption per unit of output in real time.
The main task in developing a control system is the selection of parameters involved in control, that is, those parameters that need to be monitored, regulated and by analyzing the change in values of which it is possible to determine the pre-emergency state of the technological control object (TOU).
The parameters subject to control are those whose values are used to carry out operational control of the technological process (TP), as well as the start and stop of technological units.
4.1 Pressure measurement
pressure and vacuum meters; pressure meters (for measuring small (up to 5000 Pa) excess pressures); draft meters (for measuring small (up to hundreds of Pa) vacuums); thrust gauges; differential pressure gauges (for measuring pressure differences); barometers (for measuring atmospheric pressure). According to the principle of operation, the following instruments for measuring pressure are distinguished: liquid, spring, piston, electric and radioactive.
For measuring gas and air pressure up to 500 mm water. Art. (500 kgf/m2) use a glass U-shaped liquid pressure gauge. The pressure gauge is a glass U-shaped tube attached to a wooden (metal) panel that has a scale marked in millimeters. The most common pressure gauges have scales of 0-100, 0-250 and 0-640 mm. The pressure value is equal to the sum of the heights of the liquid levels lowered below and raised above zero.
In practice, pressure gauges with a double scale are sometimes used, in which the division value is halved and the numbers from zero up and down go with an interval of 20: 0-20-40-60, etc. in this case, there is no need to indicate the heights of liquid levels , it is enough to measure the pressure gauge readings at the level of one bend of the glass tube. Measurement of small pressures or vacuums up to 25 mm of water. Art. (250 Pa) single-pipe or U-shaped liquid pressure gauges leads to large errors when reading measurement results. To increase the scale of the readings of a single-tube pressure gauge, the tube is tilted. TNZh liquid draft pressure meters operate on this principle, which are filled with alcohol with a density of r = 0.85 g/cm3. in them, liquid is forced out of a glass vessel into an inclined tube along which there is a scale graduated in mm of water. Art. When measuring vacuum, the pulse is connected to a fitting that is connected to an inclined tube, and when measuring pressure, it is connected to a fitting that is connected to a glass vessel. Spring pressure gauges. To measure pressure from 0.6 to 1600 kgf/cm2, spring pressure gauges are used. The working element of the pressure gauge is a curved tube of ellipsoidal or oval cross-section, which is deformed under the influence of pressure. One end of the tube is sealed, and the other is connected to a fitting that is connected to the medium being measured. The closed end of the tube is connected through a rod to the gear sector and the central gear wheel, on the axis of which an arrow is mounted.
The pressure gauge is connected to the boiler through a siphon tube in which steam is condensed or water is cooled and pressure is transmitted through the cooled water, which prevents damage to the mechanism from the thermal action of steam or hot water, and the pressure gauge is also protected from water hammer.
In this process, it is advisable to use a Metran-55 pressure sensor. The selected sensor is ideal for measuring the flow of liquid, gas, steam. This sensor has the required measurement limits - min. 0-0. 06 MPa to max. 0-100 MPa. Provides the required accuracy of 0.25%. It is also very important that this sensor has an explosion-proof design, the output signal is unified - 4 -20 mA, which is convenient when connecting a secondary device since it does not require additional installation of an output signal converter. The sensor has the following advantages: 10:1 reconfiguration range, continuous self-diagnosis, built-in radio interference filter. Microprocessor electronics, the ability to simply and conveniently configure parameters with 2 buttons.
The measured pressure is supplied to the working cavity of the sensor and acts directly on the measuring membrane of the strain gauge transducer, causing it to deflect.
The sensitive element is a single-crystal sapphire plate with silicon film strain gauges. Connected to the metal plate of the strain gauge transducer. The strain gauges are connected in a bridge circuit. Deformation of the measuring membrane leads to a proportional change in the resistance of the strain gauge and imbalance of the bridge circuit. The electrical signal from the output of the sensor bridge circuit enters the electronic unit, where it is converted into a unified current signal.
The sensor has two operating modes:
Pressure measurement mode; - mode for setting and monitoring measurement parameters.
In pressure measurement mode, the sensors provide constant monitoring of their operation and, in the event of a malfunction, generate a message in the form of a decrease in the output signal below the limit.
4.2 Temperature measurement
One of the parameters that must not only be monitored, but also signaled as the maximum permissible value is temperature.
resistance thermometers and radiation pyrometers.
In boiler rooms, instruments are used to measure temperature, the operating principle of which is based on the properties exhibited by substances when heated: Change in volume - expansion thermometers; Pressure change – manometric thermometers; The emergence of thermoEMF - thermoelectric pyrometers;
Changes in electrical resistance - resistance thermometers.
extensions are used for local temperature measurements ranging from -190 to +6000C. The main advantages of these thermometers are simplicity, low cost and accuracy. These instruments are often used as reference instruments. Disadvantages - impossibility of repair, lack of automatic recording and the ability to transmit readings over a distance. The measurement limits of bimetallic and dilatometric thermometers are from – 150 to +700 0С, error 1-2%. Most often they are used as sensors for automatic control systems.
Manometric thermometers. Used for remote temperature measurement. The principle of their operation is based on changing the pressure of liquids, gas or steam in a closed volume depending on temperature.
The type of working substance determines the type of manometric thermometer:
Gas – with inert gas (nitrogen, etc.)
Their advantage is simplicity of design and maintenance, the possibility of remote measurement and automatic recording of readings. Other advantages include their explosion safety and insensitivity to external magnetic and electric fields. Disadvantages are low accuracy, significant inertia and a relatively short distance for remote transmission of readings.
Thermoelectric pyrometer. It is used to measure temperatures up to 16000C, as well as transmitting readings to a heat shield and consists of a thermocouple, connecting wires and a measuring device.
A thermocouple is a connection of two conductors (thermoelectrodes) made of different metals (platinum, copper) or alloys (chromel, copel, platinum-rhodium), insulated from each other by porcelain beads or tubes. Some ends of the thermoelectrodes are soldered together, forming a hot junction, while the others remain free.
For ease of use, the thermocouple is placed in a steel, copper or quartz tube.
When the hot junction is heated, a thermoelectromotive force is generated, the magnitude of which depends on the temperature of the hot junction and the material and material of the thermoelectrodes.
electrical resistance of conductors or semiconductors when temperature changes. Resistance thermal converters: platinum (RTC) are used for long-term measurements in the range from 0 to +650 0C; copper (TCM) for measuring temperatures in the range from –200 to +200 0C. Automatic electronic balanced bridges with an accuracy class of 0.25 to 0.5 are used as secondary devices. Semiconductor resistance thermometers (thermistors) are made from oxides of various metals with additives. The most widely used are cobalt-manganese (CMT) and copper-manganese (MMT) semiconductors, used for measuring temperatures in the range from – 90 to +300 0C. Unlike conductors, the resistance of thermistors decreases exponentially with increasing temperature, making them highly sensitive. However, it is almost impossible to produce thermistors with strictly identical characteristics, so they are calibrated individually. Resistance thermal converters, complete with automatic electronic balanced bridges, allow you to measure and record temperature with high accuracy, as well as transmit information over long distances. The most widely used primary measuring converters of such thermometers are currently: platinum-rhodium - platinum (TPP) converters with measurement limits from – 20 to + 1300 0С; chromel-copel (TCA) converters with measurement limits from – 50 to + 600 0С and chromel-alumel (TCA) converters with measurement limits from – 50 to + 1000 0С. For short-term measurements, the upper temperature limit for the TXK converter can be increased by 200 0C, and for the TPP and TXA converters by 300 0C. To measure temperature on pipelines and on boilers, I decided to choose thermoelectric converters of the TXA type - the choice of these particular converters is due to the fact that in the measurement range from –50 to +600 0C it has a higher sensitivity than the TXA converter. The main characteristics of the thermoelectric converter type THK - 251 manufactured by CJSC PG "Metran":
· Purpose: for measuring temperatures of gaseous and liquid media;
· Range of measured temperatures: from – 40 to +600 0С;
· The length of the mounting part of the converter is 320 mm;
· Protective cover material; stainless steel, grade 12Х18Н10Т, and its diameter is 10 mm;
· Average service life of at least 2 years;
· Sensing element: thermocouple cable KTMS-HK TU16-505. 757-75;
4.3 Level measurement
The level is the height of filling of a technological apparatus with a working medium - liquid or granular solid. The level of the working environment is a technological parameter, information about which is necessary to control the operating mode of the technological apparatus, and in some cases to control the production process.
By measuring the level, you can obtain information about the mass of liquid in the tank. Level is measured in units of length. The measuring instruments are called level gauges.
There are level gauges designed to measure the level of the working environment; measuring the mass of liquid in a technological apparatus; signaling limit values of the level of the working environment - level switches.
Based on the measurement range, level gauges are divided into wide and narrow ranges. Wide range level gauges (with measurement limits of 0.5 - 20 m) are designed for inventory accounting operations, and narrow range level gauges (measurement limits of (0÷ ±100) mm or (0÷ ±450) mm) are usually used in automatic control systems.
Currently, level measurement in many industries is carried out by level gauges of various operating principles, of which float, buoy, hydrostatic, electric, ultrasonic and radioisotope are widespread. Visual measuring instruments are also used.
Indicator or level glasses are made in the form of one or several chambers with flat glasses connected to the apparatus. The operating principle is based on the property of communicating vessels. Used for local level measurement. The length of the glass does not exceed 1500 mm. The advantages include simplicity, high accuracy: disadvantages - fragility, inability to transmit readings over a distance.
When calculating float level gauges, design parameters of the float are selected that ensure the state of equilibrium of the “float-counterweight” system only at a certain immersion depth of the float. If we neglect the gravity of the cable and the friction in the rollers, the equilibrium state of the float-counterweight system is described by the equation
where Gr, Gп – gravity forces of the counterweight and float; S - float area; h1 – float immersion depth; pl is the density of the liquid.
An increase in the liquid level changes the immersion depth of the float and an additional buoyant force acts on it.
The advantage of these level meters is their simplicity, fairly high measurement accuracy, the ability to transmit over a distance, and the ability to work with aggressive liquids. A significant disadvantage is the sticking of a viscous substance to the float, which affects the measurement error.
The principle of operation of capacitive level meters is based on the change in the capacitance of the converter due to changes in the level of the controlled environment. The measurement limits of these level gauges are from 0 to 5 meters, the error is no more than 2.5%. Information can be transmitted over a distance. The disadvantage of this method is the inability to work with viscous and crystallizing liquids.
The operating principle of hydrostatic level gauges is based on measuring the pressure created by a liquid column. Hydrostatic pressure is measured:
· a pressure gauge connected at a height corresponding to the lower limit value of the level;
· by measuring the pressure of gas pumped through a tube lowered into the liquid filling the tank at a fixed distance.
In our case, the most suitable are water indicator devices with round and flat glass, lowered level indicators and water testing taps. Water indicators with round glass are installed on boilers and tanks with a pressure of up to 0.7 kgf/cm2. glass height can be from 200 to 1500 mm, diameter - 8 -20 mm, glass thickness 2.5-3.5 mm. Flat glass can be smooth or grooved. Klinger glass has vertical prismatic grooves on the inside and is polished on the outside. In such glass, water appears dark and steam appears light. If during operation of the steam boiler the taps of the water indicating device are not dirty, then the water level in it fluctuates slightly.
4.4 Flow measurement
One of the most important parameters of technological processes is the flow rate of substances flowing through pipelines. The means that measure the consumption and quantity of substances during commodity accounting operations are subject to high accuracy requirements.
Let's consider the main types of flowmeters: variable pressure differential flowmeters, constant differential pressure flowmeters, tachometer flowmeters, velocity pressure flowmeters, electromagnetic (induction) flowmeters, ultrasonic.
One of the most common principles for measuring the flow of liquids, gases and steam is the variable pressure principle.
The operating principle of constant differential pressure flowmeters is based on vertical movement of the sensing element depending on the flow rate of the substance, while the flow area changes so that the pressure drop across the sensing element remains constant. The main condition for correct reading is the strictly vertical installation of the rotameter.
Flow meters. Flow meters belong to a large group of flow meters, also called constant differential pressure flow meters. In these flow meters, a streamlined body perceives a force action from the oncoming flow, which, as the flow rate increases, increases and moves the streamlined body, as a result of which the moving force decreases and is again balanced by the opposing force. The counteracting force is the weight of the streamlined body when the flow moves vertically from bottom to top, or the force of the counteracting spring in the case of an arbitrary flow direction. The output signal of the flow transducers under consideration is the movement of the streamlined body. To measure the flow of gases and liquids on process streams, rotameters are used, equipped with converting elements with an electrical or pneumatic output signal.
Liquid flows out of the vessel through a hole in the bottom or side wall. Vessels for receiving liquid are made cylindrical or rectangular.
a thin disk (washer) with a cylindrical hole, the center of which coincides with the center of the cross-section of the pipeline, the device measuring the pressure difference and connecting tubes. The summing device determines the flow rate of the medium based on the rotation speed of the impeller or rotor installed in the housing.
To measure gas and steam flow, I chose a Rosemount 8800DR smart vortex flow meter with built-in conical adapters, which reduces installation costs by 50%. The operating principle of a vortex flow meter is based on determining the frequency of vortices formed in the flow of the measured medium when flowing around a body of a special shape. The vortex frequency is proportional to the volume flow. It is suitable for measuring the flow of liquid, steam and gas. For digital and pulse output, the basic permissible error limit is ±0. 65%, and for current additionally ±0. 025%, output signal 4 - 20 mA. The advantages of this sensor include a non-clogging design, the absence of impulse lines and seals increases reliability, increased resistance to vibration, the ability to replace sensors without stopping the process, and short response time. Possibility of simulating verification; there is no need to narrow the pipeline during operation. A-100 can be used as a secondary device. To measure water flow, we use a correlation water flow sensor DRK-4. The sensor is designed to measure the flow and volume of water in completely filled pipelines. Main advantages:
· lack of flow resistance and pressure loss;
· possibility of mounting primary transducers on the pipeline at any orientation relative to its axis;
· correction of readings taking into account inaccuracy of installation of primary transducers;
· spill-free, simulation verification method;
· intercheck interval – 4 years;
· unified current signal 0-5.4-20 mA;
· self-diagnosis;
temperature of liquid fuel in the common pressure line; steam pressure in the line for spraying liquid fuel; pressure of liquid or gaseous fuel in common pressure lines; consumption of liquid or gaseous fuel in the boiler room as a whole. The boiler room must also provide for recording the following parameters: the temperature of superheated steam intended for technological needs; water temperature in the supply pipelines of the heating network and hot water supply, as well as in each return pipeline; steam pressure in the supply manifold; water pressure in the return pipeline of the heating network; steam flow in the supply manifold; water flow in each supply pipeline of the heating network and hot water supply; water consumption used to recharge the heating network. Deaerator-feeding installations are equipped with indicating instruments for measuring: water temperature in storage and feed tanks or in the corresponding pipelines; steam pressure in deaerators; feed water pressure in each line; water pressure in the suction and pressure pipes of feed pumps; water level in battery and feed tanks.
| Controlled parameter | Availability of indicating devices on boilers | |||
| <0,07 | >0,07 | <115 | >115 | |
|
4. Flue gas temperature behind the boiler 6. Steam pressure in the boiler drum 7. Steam (water) pressure after the superheater (after the boiler) 8. Steam pressure supplied to fuel oil spraying 9. Water pressure at the boiler inlet 11. Air pressure after the blower fan 12. Air pressure in front of the burners (after the control dampers) 15. Vacuum in front of the smoke exhaust valve or in the flue 16. Vacuum before and behind the tail heating surfaces 18. Water flow through the boiler (for boilers with a capacity of more than 11.6 MW (10 Gcal/h)) 19. Level in the boiler drum |
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*For boilers with a capacity of less than 0.55 kg/s (2 t/h) – pressure in the common feed line 6. Basic information about fuel.
Fuel refers to combustible substances that are burned to produce heat. According to the physical state, fuel is divided into solid, liquid and gaseous. Gaseous gases include natural gas, as well as various industrial gases: blast furnace, coke oven, generator and others. High-quality fuels include coal, anthracite, liquid fuel and natural gas. All types of fuel consist of combustible and non-combustible parts. The combustible part of the fuel includes: carbon C, hydrogen H2, sulfur S. The non-combustible part includes: oxygen O2, nitrogen N2, moisture W and ash A. The fuel is characterized by working, dry and combustible masses. Gas fuel is most convenient for mixing it with air, which is necessary for combustion, since fuel and air are in the same state of aggregation.
5. Physico-chemical properties of natural gases
Natural gases are colorless, odorless and tasteless. The main indicators of combustible gases that are used in boiler houses: composition, calorific value, density, combustion and ignition temperature, explosion limits and flame propagation speed. Natural gases from pure gas fields consist mainly of methane (82-98%) and other heavier hydrocarbons. The composition of any gaseous fuel includes flammable and non-flammable substances. Combustibles include: hydrogen (H2), hydrocarbons (CmHn), hydrogen sulfide (H2S), carbon monoxide (CO2), non-flammable ones include carbon dioxide (CO2), oxygen (O2), nitrogen (N2) and water vapor (H2O). Heat of combustion - the amount of heat that is released during the complete combustion of 1 m3 of gas, measured in kcal/m3 or kJ/m3. There is a distinction between the highest calorific value Qвc, when the heat released during the condensation of water vapor that is in the flue gases is taken into account, and the lowest calorific value Qнc, when this heat is not taken into account. When performing calculations, Qwc is usually used, since the temperature of the flue gases is such that condensation of water vapor from combustion products does not occur. The density of a gaseous substance is determined by the ratio of the mass of the substance to its volume. Density unit kg/m3. The ratio of the density of a gaseous substance to the density of air under the same conditions (pressure and temperature) is called the relative gas density pо. Gas density pr= 0.73 - 0.85 kg/m3 (pо = 0.57-0.66) The combustion temperature is the maximum temperature that can be achieved during complete combustion of the gas, if the amount of air required for combustion exactly corresponds chemical combustion formulas, and the initial temperature of gas and air is 0 °C, and this temperature is called the heat output of the fuel. The combustion temperature of individual gases is 2000-2100 o C. The actual combustion temperature in boiler furnaces is much lower, 1100-1600 o C and depends on the combustion conditions. The ignition temperature is the temperature at which fuel combustion begins without the influence of an ignition source; for natural gas it is 645-700 o C. Explosive limits. A gas-air mixture containing up to 5% gas does not burn; from 5 to 15% - explodes; more than 15% - burns when air is supplied. Flame propagation speed for natural gas is 0.67 m/s (methane CH4). The use of natural gas requires special precautions, since it can leak through leaks at the junction of the gas pipeline with gas fittings. The presence of more than 20% of the gas in a room causes suffocation; its accumulation in a closed volume of 5 to 15% can lead to an explosion of the gas-air mixture; with incomplete combustion, carbon monoxide CO is released, which, even at low concentrations, has a poisonous effect on the human body.
6. Description of the automatic control scheme for process parameters
6. 1 Functional diagram of automatic control of process parameters
The principle of constructing a control system for this process is two-level. The first level consists of devices located locally, the second level consists of devices located on the operator’s panel.
Table 2.
Name and technical characteristics of equipment and materials. Manufacturer |
Type, brand of equipment. Designation Document and questionnaire number | Unit measurements |
Quantity |
|
| Pipeline temperature monitoring | ||||
| 1a | Gas temperature in the pipeline Thermoelectric converter |
TKhK-251-02-320-2-I-1-N10-TB-T6-U1. 1-PG |
PC. | 1 |
| 1b | Secondary indicating recording device, speed 5s, time of one revolution 8h | DISK250-4131 | PC. | 1 |
| 2a |
PG "Metran", Chelyabinsk |
TSM254-02-500-V-4-1- |
PC. | 1 |
| 2b | PC. | 1 | ||
| 2v | PRB-2M | PC. | 1 | |
| 2g | Actuator, power supply 220V, frequency 50Hz | MEO-40/25-0.25 | 1 | |
| 3a | Copper resistance thermocouple nominal static characteristic 100M |
TSM254-02-500-V-4-1- TU 422700-001-54904815-01 |
1 | |
| 3b | Electromagnetic converter, flow rate 5 l/min, output signal 20-100 kPa | EPP | 1 | |
| 3v | 1 | |||
| 3g | PR 3. 31-M1 | 1 | ||
| 3D | Actuator, nominal pressure 1.6 MPa | 25h30nzh | 1 | |
| Pipeline flow control | ||||
| 4a | Chamber diaphragm, nominal pressure 1.6 MPa | DK 16-200 | 1 | |
| 4b | Differential transducer, error 0.5%, measurement limit 0.25 MPa | Sapphire 22DD-2450 | 1 | |
| 4v | Secondary indicating recording device. Speed 5s, time of one revolution 8h. | DISC 250-4131 | 1 | |
| Flow control | ||||
| 5a | IR-61 | 1 | ||
| 5 B |
PG "Metran", Chelyabinsk Recorder, 2-channel, scale in Percents. Cl. t. 0. 5, speed 1s. |
Rosemount 8800DR A100-BBD,04. 2, TU 311--00226253. 033-93 |
1 | |
| 5v | Contactless reversible starter, discrete input signal 24V, power supply 220V, 50Hz | PBR-2M | 1 | |
| 5g | Actuator, power supply 220V, frequency 50Hz | 1 | ||
| Level regulation | ||||
| 6a | Level gauge, upper limit of measurement 6m, maximum permissible overpressure 4 MPa, supply pressure 0.14 MPa, output pneumatic signal 0.08 MPa | UB-PV | 1 | |
| 6b | Pressure gauge, power supply 220V, power 10 W | EKM-1U | 1 | |
| 6v | Secondary pneumatic indicating and recording instrument, with control station. Air consumption 600 l/h | PV 10. 1E | 1 | |
| 6g | 25h30nzh | 1 | ||
| Pressure measurement |
7. Basic principles of automation of boiler plants
The scope of boiler plant automation systems depends on the type of boilers installed in the boiler room, as well as the presence of specific auxiliary equipment in its composition. Boiler installations are equipped with the following systems: automatic control, safety automation, thermal control, alarm and electric drive control. Automatic control systems. The main types of ACP of boiler installations: for boilers - regulation of combustion and power processes; for deaerators – regulation of water level and steam pressure. Automatic control of combustion processes should be provided for all boilers operating on liquid or gaseous fuel. When using solid fuel, ACP of combustion processes is provided in cases of installation of mechanized combustion devices.
ASR fuel is not provided.
Power regulators are recommended to be installed on all steam boilers. For boiler installations operating on liquid fuel, it is necessary to provide an ACS for fuel temperature and pressure. Boilers with a steam superheat temperature of 400 0C and above must be equipped with an ASD for superheated steam temperature. Security automation. Automatic safety systems for gaseous and liquid fuel boilers should be provided. These systems ensure that the fuel supply is stopped in emergency situations.
Table3.
| Parameter deviation | Stopping the fuel supply to boilers | |||
| Steam with steam pressure piz, MPa | Hot water with water temperature, 0C | |||
| <0,07 | >0,07 | <115 | >115 | |
1. Increasing the steam pressure in the boiler drum 2. Increasing the water temperature behind the boiler 3. Reducing air pressure 4. Reducing gas pressure 5. Increasing gas pressure 6. Reducing water pressure behind the boiler 7. Reducing the vacuum in the furnace 8. Lowering or raising the level in the boiler drum 9. Reducing water consumption through the boiler 10. Extinguishing of the torch in the boiler furnace 11. Malfunction of automatic safety equipment |
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Conclusion
During the course project, practical skills were acquired in analyzing the technological process, selecting automatic control means according to the assigned tasks, calculating measuring circuits of instruments and control means. We also acquired skills in designing an automatic control system for process parameters.
Literature
1. A. S. Boronikhin Yu. S. Grizak “Fundamentals of production automation and instrumentation at enterprises of the construction materials industry” M. Stroyizdat 1974 312s.
2. V. M. Tarasyuk “Operation of boilers”, a practical guide for boiler room operators; edited by B. A. Sokolov. – M.: ENAS, 2010. – 272 p.
3. V. V. Shuvalov, V. A. Golubyatnikov “Automation of production processes in the chemical industry: Textbook. For technical schools. – 2nd ed. reworked and additional - M.: Chemistry, 1985. - 352 s. ill.
4. Makarenko V. G., Dolgov K. V. Technical measurements and instruments: Guidelines for course design. South -Rus. state tech. univ. Novocherkassk: SRSTU, 2002. – 27 p.