Do you need to PWHT fillet welds in A333 gr6 pipe
for propane duty down to -43degC (-45degF)?
As material has P No.1 pipe does not need PWHT unless thicker than 19mm (3/4") according to B31.3, but I think this might be a bit simplistic due to the low temperature?
H.P. Steam 90bar 490C (1300psi 914F)
When we have to repair pipework during shutdown if we cannot Hyd. Press. test the pipework we 100% Radiograph all Final butt welds (butt welds are the only weld we allow as final welds even down to sizes we would normally use Socket weld fittings on).
While...
We have positive displacement pumps which use mechanical seals which are designed for a Max. Inlet pressure of 3.5bar.
It has been noticed that although we can maintain the 3.5bar during normal running conditions, the thermal relief valves on the inlet piping are set at 5.5bar
Does this mean...
