Testing Propane Tank Pressure Relief Valves
Testing Propane Tank Pressure Relief Valves
(OP)
Is it possible to hydrolift test referenced PRV's on site as Utility Power Boilers Safety Valves are tested?
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Testing Propane Tank Pressure Relief Valves
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RE: Testing Propane Tank Pressure Relief Valves
PRV in LPG tanks are usually checked for set pressure during periodical hydrotest test of tanks.
This check is always done with water but procedure differs with operators.
You can test PRV on the tank fixing seat valve during hydrotest with a fastener and after then bringing down pressure on tank below set pressure, removing fastener and testing PRV increasing pressure again. This must be after hydrotest to avoid permanent fixing of valve seat.
You can test PRV on the tank too but threading to tank a gear consisting in a tube and a valve with a manometer in it.
Another way is putting PRV in this gear but connecting it directly to pump instead of threading it to tank.
In the two firts systems, as tank volume is big pressure goes up and down smooth but test fluid is always water. In third case gear volume is small and pressure lift fast and pulsating but if gear is empty full of air or you can empty it with drain valves you can test PRV with air using a water pump and pressure goes up slower.
Regards from Barcelona
G. García
RE: Testing Propane Tank Pressure Relief Valves
If you wanted to place a block valve under your PRV and install a test ring (a thick block that fits between the valve and PRV and has a 1/2" test port valve) you could do a lifting test in service. Normally, I've always taken the PRV off and had the who valve inspected to see if there is any mechanical problems. This is done on site with a company that has an ASME code shop and a portable shop.
I normally do this every 5 years, unless there was something to trigger an early inspection.
RE: Testing Propane Tank Pressure Relief Valves
Have you reviewed the requirements of the NFPA code for these valves ?
(I think it is NFPA-58 that governs these devices..)
-MJC
RE: Testing Propane Tank Pressure Relief Valves
May be you haven't seen a LPG tank hydrotested. I've seen hundreds instead. Most of them of less than 10 m3 in residential use.
All LPG tanks in spain are tested every ten or 12 years. Even big tanks in filling plants for road tanks are filled with water. Sometimes for thickness meassurements a boat is used while filling or emptying tank. Tests for this big ones include checks for changes in supports caused by weight.
As you said, "Y" fittings for two, three or more valves are used for bigger tanks than residential use and are usefull for testing or change valves with in service tank.
Regards from Barcelona
G. García
RE: Testing Propane Tank Pressure Relief Valves
RE: Testing Propane Tank Pressure Relief Valves
RE: Testing Propane Tank Pressure Relief Valves
I can't say I have experience with this but I remembered I had come across this from the Propane Council...see if it has any worthwhile info.
http:/
RE: Testing Propane Tank Pressure Relief Valves
RE: Testing Propane Tank Pressure Relief Valves
Applying a force in the sharf to set pressure and knowing force, actual pressure and surface of seat valve you may calc set pressure.
But PSV for GLP usually are internal or external Rego type valves with no shaft.
where are you going to apply force?
Regards from Barcelona
G. García