The development direction of regulating valves is mainly intelligent, standardized, refined, rotated, and safe.
Intelligentization and standardization. The intelligence and standardization of regulating valves have been mentioned on the agenda. Intelligent mainly uses intelligent valve positioners. Intelligence is manifested in the following aspects.
1 The self-diagnosis of the regulating valve and the intelligent functions such as the remote communication in the running state make the management of the regulating valve convenient, the fault diagnosis becomes easy, and the skill requirements for maintenance personnel are also reduced.
2 Reduce product types and simplify production processes. Using a smart valve positioner can not only easily change the flow characteristics of the regulating valve, but also improve the control quality of the control system. Therefore, the requirements on the flow characteristics of the regulating valve can be simplified and standardized (for example, only the linear characteristic regulating valve is produced). The intelligent function module is used to achieve the matching with the characteristics of the controlled object, so that the type and variety of the regulating valve product are greatly reduced. The manufacturing process of the regulating valve is simplified and tested and approved in production and in the market.
3 digital communications. Digital communication will be widely used in regulating valves. Based on the HART communication protocol, some valve positioners of the regulating valve will implement input signals and valve position signals on the same transmission line; based on fieldbus technology, control valves and valve positioners The combination of PID control function modules enables the control function to be implemented at the field level, which spreads the danger and makes the control more timely and more rapid.
4 smart valve positioner. The intelligent valve positioner has all the functions of the valve positioner. At the same time, it can improve the dynamic and static characteristics of the regulating valve and improve the control accuracy of the regulating valve. Therefore, the intelligent valve positioner will become an important auxiliary valve for the regulating valve in the next period of time. widely used.
The standardization of the regulating valve is manifested in the following aspects.
1 In order to achieve interchangeability, the regulating valves produced by different manufacturers of the same size and specification can be interchanged, so that the user does not have to spend a lot of time selecting the manufacturer.
2 In order to achieve interoperability, regulators manufactured by different manufacturers should be able to work in concert with other manufacturers' products without signal mismatch or impedance mismatch.
3 Standardized diagnostic software and other auxiliary software enable different manufacturer's regulating valves to perform diagnostics of operational status and analysis of operational data.
4 standardized selection process. The selection of control valve is still a matter of great concern to automation designers. Using standardized calculation procedures, according to the data provided by the process, the flow coefficient of the required regulating valve can be correctly calculated, the piping can be determined, and the appropriate valve body, valve core and valve can be selected. Internal materials, etc., standardize the design process and improve design quality.
(2) Miniaturization. In order to reduce the weight of the regulating valve and to facilitate transportation, installation and maintenance, the following measures have been adopted for the miniaturization of the regulating valve.
1 Use fine-scale actuators. Using lightweight materials, multiple sets of springs are used instead of one set of springs to reduce the height of the actuator. Usually, the control valve consisting of fine pneumatic actuators is reduced in height by approximately 30% compared to the same type of pneumatic diaphragm actuator. About 30% lower, while circulation capacity can be increased by about 30%.
2 Change the flow path structure. For example, the movement of the valve element is changed to the movement of the valve seat, and the linear displacement is changed to the angular displacement, so that the regulating valve is reduced in size and the weight is reduced.
3 using electric actuators. It can not only reduce the air source device and auxiliary equipment needed for pneumatic actuators, but also reduce the weight of the actuator. For example, Fisher's Series 9000 Electric Actuators have a height of less than 330 mm in the Type 20, which reduces the overall control valve (with digital controller and actuator) to 20 to 32 kg.
(3) Rotation Due to rotary type control valves, such as ball valves, etc., there are advantages such as smaller relative volume, smaller flow path resistance, larger adjustment, better sealability, better anti-blocking performance, and larger flow capacity. Therefore, in the new type of regulating valve, the specific gravity of the rotary valve increases. Especially in large-diameter pipes, ball valves, butterfly valves, and other type control valves are commonly used. From the perspective of foreign products in recent years, the proportion of rotary valve applications is increasing year by year.
(4) The safety of the safety instrumentation control system has been paid attention to by various parties. The requirements of the safety instrumentation system (SIS) for the control valve are also increasing, which is manifested in the following aspects.
1 The diagnosis and processing requirements of the fault information of the regulating valve are improved, not only the passive maintenance of the regulating valve after the fault occurs, but also the preventive maintenance and predictive maintenance before the fault occurs. Therefore, it is more important to statistically analyze and analyze the components that make up the regulating valve, and to propose maintenance proposals in a timely manner.
2 The requirements for timely, reliable and safe operation of the regulating valve used for the emergency stop system or safety interlock system. Make sure these regulators are responsive and accurate.
3 For regulators used in hazardous locations, the certification procedure should be simplified. For example, fieldbus instrumentation for intrinsically safe applications can be simplified to use the intrinsic safety concept of the FISCO fieldbus, which simplifies the certification process for intrinsically safe products.
4 Similar to the safety of other on-site instruments, the safety of regulating valves can be flameproof technology, fireproof technology, safety-enhancing technology, intrinsically safe technology, and non-sparking technology. For field bus instrumentation, physical concepts can also be used. Intrinsically safe concept, FISCO concept and non-flammable (FINCO) concept.
(5) Energy saving Reducing energy consumption and improving energy efficiency are a development direction of the regulating valve. There are mainly the following development directions.
1 Use a low pressure drop ratio regulator. Reduce the proportion of the regulating valve in the pressure drop of the entire system, thereby reducing energy consumption. Therefore, the design of the low pressure drop ratio regulator valve is one of the directions of development; another development direction is the use of low impedance regulator valve, such as the use of butterfly valve, eccentric Rotary valve and so on.
2 using self-regulating valve. For example, the pressure of the medium directly behind the valve is used to form a self-operated control system, and the pressure of the valve is controlled by the energy of the controlled medium.
3 using electric actuator control valve. Pneumatic actuators require a certain amount of air pressure during the operation of the entire regulating valve. Although small amounts of amplifiers can be used, the air consumption is still huge. With electric actuators, power supply is needed to change the opening degree of the regulating valve. When the required opening degree is reached, power supply is no longer possible. Therefore, from the viewpoint of energy saving, the electric actuator has obvious energy-saving advantages over the pneumatic actuator.
4 using piezoelectric control valve. Piezoelectric control valves are used in smart electric valve positioners, which consume air only when the output signal increases.
5 Use a valve core with a balanced structure to reduce the thrust or pushing torque of the actuator, reduce the membrane air chamber, and reduce energy requirements.
6 The use of frequency control technology instead of regulating valve. For high pressure drop ratio applications, if the energy consumption is large, variable frequency speed control technology can be used, and the inverter can be used to change the rotational speed of the operating equipment and reduce energy consumption.
(6) Protection of the environment The pollution of the environment has become a public hazard. The pollution of the regulating valve to the environment is mainly caused by the noise of the regulating valve and the leakage of the regulating valve. Among them, the pollution of the regulating valve to the environment is even more serious.
1 Reduce the noise of the regulating valve. Develop various methods to reduce the noise of regulating valves, from the design of the flow path of the regulating valve to the design of the valve trim of the regulating valve, from the analysis of noise sources to the measures to reduce noise. Mainly include the design of noise reduction control valves and noise reduction regulator valve trims; reasonable distribution of pressure drop, the use of external noise reduction measures, for example, increase the isolation, the use of muffler and so on.
2 Reduce the air pollution of the regulating valve. The air pollution of the regulating valve refers to the “runâ€, “burâ€, “dripâ€, and “leakage†of the regulating valve. These leakages not only cause the waste of materials or products, but also cause pollution to the atmosphere, and sometimes cause people’s Casualties or equipment explosions. Therefore, the development of regulating valve packing structure and packing type, development of the sealing of the regulating valve, etc. will be an important research topic for the regulating valve in the future.
The development of high-tech science and technology such as computer science, control theory, and automation instrumentation has promoted the development of regulating valves, such as the development of fieldbus regulators and smart valve positioners, and the realization of digital communications in regulating valves. The development of regulating valves has also promoted the development of other science and technology, for example, research on anti-corrosion materials, research on ways to weaken and reduce noise, and research on fluid dynamics. With the development of fieldbus technology, the regulating valve will also be open, intelligent and more reliable. Together with other industrial automation instruments and computer control devices, it will enable the industrial production process control function to be more complete, and the control accuracy will be higher. The effect is more pronounced and will play a more important role in China's modernization construction.
Intelligentization and standardization. The intelligence and standardization of regulating valves have been mentioned on the agenda. Intelligent mainly uses intelligent valve positioners. Intelligence is manifested in the following aspects.
1 The self-diagnosis of the regulating valve and the intelligent functions such as the remote communication in the running state make the management of the regulating valve convenient, the fault diagnosis becomes easy, and the skill requirements for maintenance personnel are also reduced.
2 Reduce product types and simplify production processes. Using a smart valve positioner can not only easily change the flow characteristics of the regulating valve, but also improve the control quality of the control system. Therefore, the requirements on the flow characteristics of the regulating valve can be simplified and standardized (for example, only the linear characteristic regulating valve is produced). The intelligent function module is used to achieve the matching with the characteristics of the controlled object, so that the type and variety of the regulating valve product are greatly reduced. The manufacturing process of the regulating valve is simplified and tested and approved in production and in the market.
3 digital communications. Digital communication will be widely used in regulating valves. Based on the HART communication protocol, some valve positioners of the regulating valve will implement input signals and valve position signals on the same transmission line; based on fieldbus technology, control valves and valve positioners The combination of PID control function modules enables the control function to be implemented at the field level, which spreads the danger and makes the control more timely and more rapid.
4 smart valve positioner. The intelligent valve positioner has all the functions of the valve positioner. At the same time, it can improve the dynamic and static characteristics of the regulating valve and improve the control accuracy of the regulating valve. Therefore, the intelligent valve positioner will become an important auxiliary valve for the regulating valve in the next period of time. widely used.
The standardization of the regulating valve is manifested in the following aspects.
1 In order to achieve interchangeability, the regulating valves produced by different manufacturers of the same size and specification can be interchanged, so that the user does not have to spend a lot of time selecting the manufacturer.
2 In order to achieve interoperability, regulators manufactured by different manufacturers should be able to work in concert with other manufacturers' products without signal mismatch or impedance mismatch.
3 Standardized diagnostic software and other auxiliary software enable different manufacturer's regulating valves to perform diagnostics of operational status and analysis of operational data.
4 standardized selection process. The selection of control valve is still a matter of great concern to automation designers. Using standardized calculation procedures, according to the data provided by the process, the flow coefficient of the required regulating valve can be correctly calculated, the piping can be determined, and the appropriate valve body, valve core and valve can be selected. Internal materials, etc., standardize the design process and improve design quality.
(2) Miniaturization. In order to reduce the weight of the regulating valve and to facilitate transportation, installation and maintenance, the following measures have been adopted for the miniaturization of the regulating valve.
1 Use fine-scale actuators. Using lightweight materials, multiple sets of springs are used instead of one set of springs to reduce the height of the actuator. Usually, the control valve consisting of fine pneumatic actuators is reduced in height by approximately 30% compared to the same type of pneumatic diaphragm actuator. About 30% lower, while circulation capacity can be increased by about 30%.
2 Change the flow path structure. For example, the movement of the valve element is changed to the movement of the valve seat, and the linear displacement is changed to the angular displacement, so that the regulating valve is reduced in size and the weight is reduced.
3 using electric actuators. It can not only reduce the air source device and auxiliary equipment needed for pneumatic actuators, but also reduce the weight of the actuator. For example, Fisher's Series 9000 Electric Actuators have a height of less than 330 mm in the Type 20, which reduces the overall control valve (with digital controller and actuator) to 20 to 32 kg.
(3) Rotation Due to rotary type control valves, such as ball valves, etc., there are advantages such as smaller relative volume, smaller flow path resistance, larger adjustment, better sealability, better anti-blocking performance, and larger flow capacity. Therefore, in the new type of regulating valve, the specific gravity of the rotary valve increases. Especially in large-diameter pipes, ball valves, butterfly valves, and other type control valves are commonly used. From the perspective of foreign products in recent years, the proportion of rotary valve applications is increasing year by year.
(4) The safety of the safety instrumentation control system has been paid attention to by various parties. The requirements of the safety instrumentation system (SIS) for the control valve are also increasing, which is manifested in the following aspects.
1 The diagnosis and processing requirements of the fault information of the regulating valve are improved, not only the passive maintenance of the regulating valve after the fault occurs, but also the preventive maintenance and predictive maintenance before the fault occurs. Therefore, it is more important to statistically analyze and analyze the components that make up the regulating valve, and to propose maintenance proposals in a timely manner.
2 The requirements for timely, reliable and safe operation of the regulating valve used for the emergency stop system or safety interlock system. Make sure these regulators are responsive and accurate.
3 For regulators used in hazardous locations, the certification procedure should be simplified. For example, fieldbus instrumentation for intrinsically safe applications can be simplified to use the intrinsic safety concept of the FISCO fieldbus, which simplifies the certification process for intrinsically safe products.
4 Similar to the safety of other on-site instruments, the safety of regulating valves can be flameproof technology, fireproof technology, safety-enhancing technology, intrinsically safe technology, and non-sparking technology. For field bus instrumentation, physical concepts can also be used. Intrinsically safe concept, FISCO concept and non-flammable (FINCO) concept.
(5) Energy saving Reducing energy consumption and improving energy efficiency are a development direction of the regulating valve. There are mainly the following development directions.
1 Use a low pressure drop ratio regulator. Reduce the proportion of the regulating valve in the pressure drop of the entire system, thereby reducing energy consumption. Therefore, the design of the low pressure drop ratio regulator valve is one of the directions of development; another development direction is the use of low impedance regulator valve, such as the use of butterfly valve, eccentric Rotary valve and so on.
2 using self-regulating valve. For example, the pressure of the medium directly behind the valve is used to form a self-operated control system, and the pressure of the valve is controlled by the energy of the controlled medium.
3 using electric actuator control valve. Pneumatic actuators require a certain amount of air pressure during the operation of the entire regulating valve. Although small amounts of amplifiers can be used, the air consumption is still huge. With electric actuators, power supply is needed to change the opening degree of the regulating valve. When the required opening degree is reached, power supply is no longer possible. Therefore, from the viewpoint of energy saving, the electric actuator has obvious energy-saving advantages over the pneumatic actuator.
4 using piezoelectric control valve. Piezoelectric control valves are used in smart electric valve positioners, which consume air only when the output signal increases.
5 Use a valve core with a balanced structure to reduce the thrust or pushing torque of the actuator, reduce the membrane air chamber, and reduce energy requirements.
6 The use of frequency control technology instead of regulating valve. For high pressure drop ratio applications, if the energy consumption is large, variable frequency speed control technology can be used, and the inverter can be used to change the rotational speed of the operating equipment and reduce energy consumption.
(6) Protection of the environment The pollution of the environment has become a public hazard. The pollution of the regulating valve to the environment is mainly caused by the noise of the regulating valve and the leakage of the regulating valve. Among them, the pollution of the regulating valve to the environment is even more serious.
1 Reduce the noise of the regulating valve. Develop various methods to reduce the noise of regulating valves, from the design of the flow path of the regulating valve to the design of the valve trim of the regulating valve, from the analysis of noise sources to the measures to reduce noise. Mainly include the design of noise reduction control valves and noise reduction regulator valve trims; reasonable distribution of pressure drop, the use of external noise reduction measures, for example, increase the isolation, the use of muffler and so on.
2 Reduce the air pollution of the regulating valve. The air pollution of the regulating valve refers to the “runâ€, “burâ€, “dripâ€, and “leakage†of the regulating valve. These leakages not only cause the waste of materials or products, but also cause pollution to the atmosphere, and sometimes cause people’s Casualties or equipment explosions. Therefore, the development of regulating valve packing structure and packing type, development of the sealing of the regulating valve, etc. will be an important research topic for the regulating valve in the future.
The development of high-tech science and technology such as computer science, control theory, and automation instrumentation has promoted the development of regulating valves, such as the development of fieldbus regulators and smart valve positioners, and the realization of digital communications in regulating valves. The development of regulating valves has also promoted the development of other science and technology, for example, research on anti-corrosion materials, research on ways to weaken and reduce noise, and research on fluid dynamics. With the development of fieldbus technology, the regulating valve will also be open, intelligent and more reliable. Together with other industrial automation instruments and computer control devices, it will enable the industrial production process control function to be more complete, and the control accuracy will be higher. The effect is more pronounced and will play a more important role in China's modernization construction.