Mozzie
Mechanical
- Jul 20, 2003
- 4
Hello All, we recently detected a hydrocarbon gas leak on our facility due to pilot valve o-ring failure on a gas compression PSV.
The pilot valve spring housing is designed with a weep hole. The idea is that in the event that the internal pilot valve o-rings at the top of the stem fail, the pressure will not build up in the housing thus affecting the spring setting and also potentially overpressuring the housing.
This makes sense but gas venting uncontrollably out of the weep hole is not an ideal situation. I have contacted the supplier and there is seemingly no way around this. The housing is not strong enough to faciliate threading of the weep hole and tubing it to a safe location. Apparently, this is typical of most pilot operated PSVs.
Does anyone know of a pilot valve design which incorporates a safe system of venting gas in the event of a pilot valve o-ring failure?
The pilot valve spring housing is designed with a weep hole. The idea is that in the event that the internal pilot valve o-rings at the top of the stem fail, the pressure will not build up in the housing thus affecting the spring setting and also potentially overpressuring the housing.
This makes sense but gas venting uncontrollably out of the weep hole is not an ideal situation. I have contacted the supplier and there is seemingly no way around this. The housing is not strong enough to faciliate threading of the weep hole and tubing it to a safe location. Apparently, this is typical of most pilot operated PSVs.
Does anyone know of a pilot valve design which incorporates a safe system of venting gas in the event of a pilot valve o-ring failure?