Main Analysis: Selection and related valve control valve positioner is the main aerodynamic actuator accessories, and its supporting the use of pneumatic actuators used to improve the position accuracy of the valve to overcome the stem friction and the impact of imbalance in the media, In order to ensure that the valve regulator in accordance with the signal to achieve the correct positioning. In the following cases, with the positioner: 1, the medium pressure is high, when the pressure is large; 2, when the control valve diameter (DN> 100); 3, high temperature or low temperature control valve; 4, When the operating speed; 5, with standard signals, non-standard spring actuator (20 ~ 100KPa outside the spring range); 6, for the split-phase control; 7, the valve to achieve the reverse action And the gas open to each other conversion); 8, the need to change the flow characteristics of the valve (you can change the positioner cam); 9, no spring actuator or piston actuator, to achieve the proportion of action; Body, must be power distribution - gas valve positioner. Solenoid valve When the system needs to achieve program control or two-position control, it needs to be equipped with a solenoid valve. Selection of solenoid valve, in addition to account to pay, DC power supply and voltage and frequency, we must pay attention to the relationship between the solenoid valve and regulating valve type can be used with "normally open type" or "normally closed type." If it is required to increase the capacity of the solenoid valve to shorten the operation time, two solenoid valves can be used in parallel or the solenoid valve can be used in combination with a large capacity pneumatic relay as a pilot valve. I plant production control valve is usually used with the electromagnetic valve factory in Dandong supporting the use of. Dandong solenoid valve factory to introduce Germany's HERION advanced solenoid valve technology has been made. One direct-acting two three-way single solenoid valve (including explosion-proof); A101ED-SB024000 series (specifications: 3,5,8,10,12,15,20,25,40,50 mm) Five) Single solenoid valve A102ED-SF025000 series (specifications: 5,8,12,15,20,25 mm). Direct acting advantages: 1. Working medium can work from 0MPa; 2. Can be used for any installation; 3. Working medium for water, gas, oil; 4. Action 槊 簟 ⑿ Read Yun incitement ?. Low power, long life Long, high frequency of operation; 6 explosion-proof head by increased installation and explosion-proof combination of user-friendly wiring. Pilot-type two three-way single-control, dual-control solenoid valve P411EI-WFM80200 series (Specifications: 6,12 mm); two five-way single-control, dual solenoid valve P413EI-WFM2630 series ). Selection of technical parameters, please see Dandong solenoid valve factory product samples. Pneumatic Relays Pneumatic Relays are a type of power amplifier that delivers air pressure signals to distant locations and eliminates hysteresis due to signal pipe extensions and is used primarily between field transmitters and regulating instruments in the central control room, Or between the regulator and the on-site regulating valve, there is also a role is to enlarge or reduce the signal. Converter converter is divided into gas - electric converter and electric - gas converter, its function is to achieve a certain relationship between gas and electric signals to convert each other, mainly used in electric signal manipulation pneumatic actuator will be 0 ~ 10mA or 4 ~ 20mA electrical signal conversion or 0 ~ 100KPa gas signal into 0 ~ 10mA or 4 ~ 20mA electrical signal. Air filter pressure reducing valve Air filter pressure reducing valve is an industrial automation instrument in the annex, its main function is to filter compressed air from the compressor to purify and pressure to stabilize the required value, can be used for various types Pneumatic instruments, solenoid valves, cylinders, spraying equipment and small pneumatic tools for air supply and regulator devices. Self-locking valve (retention valve) Self-locking valve is to maintain the valve position of a device. Pneumatic control valve When the gas source failure, the device can cut off the gas source, the membrane chamber or cylinder pressure signal to maintain the state in the moment before failure, so that the valve position is maintained at the position before the failure, from To protect the bit effect. Valve position transmitter When the control valve away from the control room in order to less than the scene can accurately understand the valve switch position, it is necessary to equip the valve position transmitter, the valve opening of the body displacement, according to certain laws into electrical signals sent Control room, this signal can be a continuous signal reflecting any opening of the valve, but also can be considered as the reverse action of the valve positioner. Stroke switch (Return) stroke switch reflects the valve switch two extreme positions, and at the same time send instructions signal device, the control room can be based on this signal, rebellion switch the state of the valve in order to take appropriate measures. Keyword Search: Control Valve