boiler safety valve rating
boiler safety valve rating
(OP)
boilers are provided with two safety valves, is each valve rated for 1/2 of the boiler capacity?
We have an existing boiler (80klbs/hr) designed for 1000 psig working pressure, but had been operating at 175 psig from the start. 20 years later, boiler was converted to high pressure operation (900 psig). Now, we want to return it back to 175 psig working pressure. Do we need to reset the safety valves? If we do not, boiler feed water pumps have to be sized for safety valve set pressure, right?
We have an existing boiler (80klbs/hr) designed for 1000 psig working pressure, but had been operating at 175 psig from the start. 20 years later, boiler was converted to high pressure operation (900 psig). Now, we want to return it back to 175 psig working pressure. Do we need to reset the safety valves? If we do not, boiler feed water pumps have to be sized for safety valve set pressure, right?





RE: boiler safety valve rating
RE: boiler safety valve rating
If you have added anything that is not rated up to 900 psi, the answer is 'Absolutly Yes, you must redo the PSV's'. Don't bother asking your Inspector.
Note that the body size of your 900# PSV's may be too small for the orifice required for proper capacity at 175#. May need completely new valves, unless you saved the old ones.
RE: boiler safety valve rating