Esperanto
Shqiptare
Euskara
Zulu
Latinus
Cymraeg
தமிழ்
Slovak
Slovak
Afrikaans
14
2022
-
06
Hydrostatic test of pressure vessels
Author:
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.
Hydrostatic test of pressure 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.
As per ASME Section Vl-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=1.3MAWP×（St/Sd）
- Ph =Test Pressure
- MAWP= Maximum Allowable Working Pressure of the vessel
- St= Allowable Stress at Test Temperature(Usually at 100°F)
- Sd=Allowable Stress at Design Temperature
- St /Sd, called "Stress Ratio"
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 MAWPx(S at test temp./ S at design temp.)
Where:
Pn = Pneumatic Test Pressure.
Previous page
Previous page
undefined
Weihai Huixin Chemical Machinery
Phone:+86-15666305701
Fax:+86-0631-5581768
Email:jerryliu@hxchem.net.cn
Address:No.159,Lili Road,Lingang,Weihai 264200,Shandong,China