Hydrostatic Test Pressure vs MAWP of Section VIII Vessels; 

An example of Hydrostatic Test Pressure compared to the MAWP of Pressure Vessel ( in the form of Shell & Tube Heat Exchanger) designed according to ASME Section VIII Div.1.

What is Hydrostatic Test Pressure for Section VIII Vessels;

The Hydrostatic Test of Pressure Vessel according to the ASME Section VIII Div.1 must be done at a pressure not less than 1.3 times of the Maximum Allowable Working Pressure (MAWP) of the Vessel multiplied by the Stress Ratio to compensate for the strength of the material. In case of use at high temperatures ( when Hydrotest is made at Ambient Temp.) , The Stress Ratio is the ratio of the Allowable Stress of the material to the Test Temp. And the Allowable Stress of the Material at the Design Temperature.