ASCo 8318D20 Solenoid Valve Leakage

[tcampbe1]

This valve is no longer supplied by ASCo, but they do supply a repair kit that works. After many years they slowly leak air from the supply to the exhaust plenums. Does anyone know specifically why? I am wondering if I can substitute say a viton o-ring in the repair kit and get longer life. The leakage is not a problem with valve actuation, but I have so many of them it taxes my compressors for air volume.

 

[hacksaw]

which repair kit are you using,

and how much air loss are you talking together with valve count

 

[tcampbe1]

The repair kit is ASCo#: 302912.

I have 72 valves, half of which have been rebuilt within the last 3 years and are still not leaking. I can't measure the air loss but my guess would be 5 to 10 SCFM.

 

[gerhardl]

Even good quality solenoid valves will leak after a number of years or a number of operations. Quality of construction, quality of process air/fluid will give largest influence on time between services, secondly quality of sealings. Asco is generally a well renowned brand, and a better selection of sealing material might help.

How does the leaking valves look inside? Impurities indicate possible improvement of pneumatic system (filters, draining). Viton is possibly not soft enough. Look for and test different available materials? Precision (accurate measurements) are important All critical sealings in the solenoid to be evaluated.