subject: Solenoid Valve Selection and Maintenance Principles [print this page] Solenoid Valve Selection and Maintenance Principles
A, Solenoid Valve Selection
A, Solenoid Valve selection of importance
Is controlled valve actuator system, the quality of its direct response to the application of the regulation of quality in the system. Process control terminal as a component in it has updated the importance of understanding than in the past. The quality of control valve applications, in addition to the quality of the product itself, the user is properly installed, use, maintenance, the correct calculation, selection is very important. Selection of calculation errors that cause the system to open to open the stop, and some can not even put into use, so for users and system designers should be aware of the importance of valves in the field, control valve selection must be taken seriously enough.
B, Solenoid Valve principle of selection
1, according to process conditions and select the appropriate structure and materials.
2, according to the technical characteristics of the object, select the Solenoid Valve flow characteristics.
3, according to process operating parameters, select the appropriate Solenoid Valve bore size.
4, according to the requirements process, select the auxiliary device.
5, reasonable choice of implementing agencies. Response speed of the implementing agencies should be able to meet the process
Control the travel time of the request: the choice of Solenoid Valve actuator valve stroke should be sounded and the process on full disclosure of the amount required level. In some cases, such as the selection pressure Solenoid Valve (including vent valve), should consider the actual differential pressure may be appropriate amplification, which would require implementing agencies to provide a larger force. Otherwise, it may appear abnormal when the process time, Solenoid Valve larger before and after the actual pressure will occur does not close or not open to danger.
Second, Solenoid Valve attachment
In the production process, the control system of the valve made a variety of special requirements, therefore, Solenoid Valve must be fitted with various attachments (the annex) to meet the needs of the production process. Solenoid Valve accessories include:
1, the valve positioner Solenoid Valve used to Fiber Optic Splice Closureimprove the regulation performance of the job characteristics, to achieve the correct positioning.
2, valve position switch shows the valve position of upper and lower stroke work.
3, the pneumatic valve when the Solenoid Valve to secure his position in the gas supply fails to keep the valve in the gas supply fails before the opening position.
4, pneumatic solenoid valve to achieve the electromagnetic switch, a power failure to ensure that the valve is in the hope that the safety valve opening position.
5, the hand wheel when the control system of the controller fails, you can switch to manually operate the valve.
6, pneumatic actuator Relay allows accelerated action to reduce the transmission time.
7, the air filter pressure reducer for the purification of air, adjust air pressure.
8, the gas tank to ensure that when the gas supply failure, so no spring piston cylinder workers Solenoid Valve actuator able to move to the fail-safe position. Its size depends on the size of the cylinder, valve and valve action time requirements of work conditions.
In short, the role of attachment Solenoid Valve function is to make better, more rational and more complete.
Third, Solenoid Valve Maintenance
Solenoid Valve has a simple structure and movement and reliable, but because it directly contacts with the process media, directly affecting the quality of its performance and environmental pollution, so Solenoid Valve must be regular maintenance and periodic maintenance, especially for the use of harsh conditions and important occasions, but should pay attention to maintenance work. Focus on examination of parts of
1, the body wall
For use in high differential pressure and corrosive media occasions Solenoid Valve, body wall, diaphragm membrane and the impact of the media are often subject to corrosion, must focus on examination of pressure, corrosion of the situation.
2, valve seat
Solenoid Valve work, because of the media into the fixed seat inner surface with a screw loose seat leaving susceptible to corrosion, inspection should be noted. Working under high pressure differential valve, check valve seat sealing surface is also washed out.
3, spool
Valve to regulate the work of moving parts, by the media, erosion, corrosion is most serious, carefully check valve when repair parts are corrosion, wear and tear, especially in the case of high-pressure differential is even more serious wear spool (due to cavitation phenomena) should be noted. Valve replacement should be carried out badly damaged, the stem should also pay attention to whether a similar phenomenon, or loose connections, etc. with the spool.
4, Patch "O" rings and other seals. Solenoid Valve shall be submitted in the diaphragm, "O"-shaped seal is aging, cracking damage.
5, sealing packing
It should be noted PTFE packing, sealing grease is aging, with the surface is damaged, should be replaced when Coach Bagsnecessary.
