Cotton21
Mechanical
- Apr 19, 2017
- 1
We have a filter housing (that is liquid full) has had a PSV installed for a fire case situation and are SCFM and not GPM. I'm a Mechanical Engineer and API Inspector (510, 570, 653) and have been for almost 15 years now. It is my understanding that you still need a PSV to protect the vessel from over pressure.
My question is do you need to have a Fire case PSV and an over pressure PSV installed concurrently?
What my thoughts are.
1. It is a pressure vessel it is required to have a PSV.
2. It is liquid so the over-pressure PSV's should be GPM and not SCFM.
3. It is being said that since the system can not over pressure this vessel that an "Over Pressure" PSV is not required. This however is not noted on the U1a. Therefore, it is required to have an over pressure PSV installed per "ASME Section VIII UG-125 and UG-140"
4. Fire case PSV's do not protect from system over-pressure.
5. PSV's that are for liquid are not interchangeable for a gas service.
Thoughts? Concerns?
My question is do you need to have a Fire case PSV and an over pressure PSV installed concurrently?
What my thoughts are.
1. It is a pressure vessel it is required to have a PSV.
2. It is liquid so the over-pressure PSV's should be GPM and not SCFM.
3. It is being said that since the system can not over pressure this vessel that an "Over Pressure" PSV is not required. This however is not noted on the U1a. Therefore, it is required to have an over pressure PSV installed per "ASME Section VIII UG-125 and UG-140"
4. Fire case PSV's do not protect from system over-pressure.
5. PSV's that are for liquid are not interchangeable for a gas service.
Thoughts? Concerns?