garfio
Mechanical
- Jul 17, 2005
- 86
Dear All:
ASME Section VIII has an exception to the rule of installing relief valves with an overpressure of 10%: UG-125 3), allows in some cases (for products like LPG and in some specific situations), to install relief valves with overpressure of 20%. One of the conditions required is that the vessel should not have “permanent supply connection”. It is clear that this is the case with all commercial tanks with LPG filled by tank trucks, however, in the case of vessels installed terminals that receive LPG through pipelines, does the multiple block valves normally installed between vessels and pipelines count to be considered as “not permanently connected”? If this is not allowed, then all vessels in LPG terminals would need valves set at 10% plus valves for fire case set at 21%.
Anybody with experience in LPG storage/terminals has an idea about what is the interpretation of the Code and what is the normal practice in these cases?
ASME Section VIII has an exception to the rule of installing relief valves with an overpressure of 10%: UG-125 3), allows in some cases (for products like LPG and in some specific situations), to install relief valves with overpressure of 20%. One of the conditions required is that the vessel should not have “permanent supply connection”. It is clear that this is the case with all commercial tanks with LPG filled by tank trucks, however, in the case of vessels installed terminals that receive LPG through pipelines, does the multiple block valves normally installed between vessels and pipelines count to be considered as “not permanently connected”? If this is not allowed, then all vessels in LPG terminals would need valves set at 10% plus valves for fire case set at 21%.
Anybody with experience in LPG storage/terminals has an idea about what is the interpretation of the Code and what is the normal practice in these cases?
