Gday Forum Members
My question relates to ASME VIII-1 2015 UG-140(b), specifically the interpretation of UG-140(b)(2) which reads:
We have multiple lube oil systems with positive displacement pumps feeding a system containing ASME VIII-1 coolers. The theoretical dead head pressure of the pump exceeds the MAWP of the cooler however it has a relief valve installed on the pump discharge to limit system pressure.
My interpretation of ASME VIII-1 UG-125 through UG-138 is that this valve would need to be UV certified as not only is it a relief valve for the pump but also a safety relief for the cooler. We don't have UV certified valves.
Does UG-140(b)(2) above allow the use of none UV certified valves? The wording is open to interpretation, firstly the clause states "overpressure protection is provided by system design per (b) if no pressure relief device compliant with UG-125 through UG-138 is to be installed." This seems to infer that protection can be as per system design if safety-relief valves are installed but not certified. However the clause then goes on to say "If no pressure relief device is to be installed, acceptance of the jurisdiction may be required." Does this relate to no device at all, or is this a continuation of the previous sentence and therefore should read "If no pressure relief device compliant with UG-125 through UG-138 is to be installed, acceptance of the jurisdiction may be required."
In summary, is it acceptable to ASME VIII-1 to have a non-certified safety-relief valve protecting ASME VIII-1 vessels and claim this as over-pressure protection by combination of system design and PSV?
Thanks for your time
My question relates to ASME VIII-1 2015 UG-140(b), specifically the interpretation of UG-140(b)(2) which reads:
(2) The decision to limit the overpressure by system design is the responsibility of the user. The user shall request that the Manufacturer’s data report state that overpressure protection is provided by system design per (b) if no pressure relief device compliant with UG-125 through UG-138 is to be installed. If no pressure relief device is to be installed, acceptance of the jurisdiction may be required.
We have multiple lube oil systems with positive displacement pumps feeding a system containing ASME VIII-1 coolers. The theoretical dead head pressure of the pump exceeds the MAWP of the cooler however it has a relief valve installed on the pump discharge to limit system pressure.
My interpretation of ASME VIII-1 UG-125 through UG-138 is that this valve would need to be UV certified as not only is it a relief valve for the pump but also a safety relief for the cooler. We don't have UV certified valves.
Does UG-140(b)(2) above allow the use of none UV certified valves? The wording is open to interpretation, firstly the clause states "overpressure protection is provided by system design per (b) if no pressure relief device compliant with UG-125 through UG-138 is to be installed." This seems to infer that protection can be as per system design if safety-relief valves are installed but not certified. However the clause then goes on to say "If no pressure relief device is to be installed, acceptance of the jurisdiction may be required." Does this relate to no device at all, or is this a continuation of the previous sentence and therefore should read "If no pressure relief device compliant with UG-125 through UG-138 is to be installed, acceptance of the jurisdiction may be required."
In summary, is it acceptable to ASME VIII-1 to have a non-certified safety-relief valve protecting ASME VIII-1 vessels and claim this as over-pressure protection by combination of system design and PSV?
Thanks for your time
