Related Resources: pressure-vessel

Hydrostatic Pressure Tests ASME Pressure Vessels

ASME Pressure Vessel Design and Engineering

ASME SECTION VIII – UG-99 – Hydrostatic Pressure Tests Pressure Vessels:

As per ASME Section VIII-1, UG-99, the pressure vessels designed for internal pressure shall be subjected to a hydrostatic test pressure which at every point in the vessel is at least equal to 1.3 times the MAWP multiplied by the lowest ratio for the materials of which the vessel is constructed of the stress value S for the test temperature on the vessel to the stress value S for the design temperature.

Ph = 1.3 MAWP x (S at test temp. / S at design temp.)

Where:

Ph = Hydrostatic Test Pressure;
MAWP = Maximum Allowable Working Pressure.

And as per UG-100, a pneumatic test (with at least equal to 1.1 times the MAWP multiplied by the lowest ratio for the materials of which the vessel is constructed of the stress value S for the test temperature on the vessel to the stress value S for the design temperature) may be used in lieu of the standard hydrostatic test prescribed in UG-99 for vessels under certain conditions:

Designed and/or supported that they cannot safely be filled with water; Not readily dried, to be used in services where traces of the testing liquid cannot be tolerated and the parts of which have, where possible, been previously tested by hydrostatic pressure to the pressure required in UG-99.

Pn = 1.1 MAWP x (S at test temp. / S at design temp.)

Where:
Pn = Pneumatic Test Pressure.