We have a Gas Chiller with a stamp that reads Temperature -50/150 Pressure 100/250 REST pressure 350 psig. The vessel is dated 1981, I know it isnt SA214 that had serious issues with low temperature. Since the chiller fluid is propane and the minimumtemperature cant really get to -50 without some serious vacuum, and all the engineering firms that designed the refrigeration system got away from using vessels with lower than 250 psig on the entire loop, I can not imagine any steel vessel that would be derated pressure wise at a lower temperature. I have seen dual temperature pressure stamps on vessels that operate at 1000 psig and 150 F, then the vessel is operated at 600 psig and 550 F with a dual stamp, but the stamp reads Pressure 110 psig at -20/150 F and 600 psig at -20/550 F not like above where the temperature and pressure are on different lines on the stamp.
So, short of going to the board, has anyone seen this stamping and the word REST PRESSURE?
So, short of going to the board, has anyone seen this stamping and the word REST PRESSURE?
