GOST Hydrotest Allowable Stress

As per ASME code, Section VIII, Division 2, Para. 8.2 Hydrostatic Testing:

8.2.1 Test Pressure

a) Except as noted for vessels of specific construction identified in paragraph 8.1.3, the minimum hydrostatic test pressure shall be the greater of:

P_T = 1.43 MAWP ……………………........... (8.1) or

P_T = 1.2 MAWP (S_T / S) ………………......(8.2)

b) The ratio S_T / S in Equation (8.2) shall be the lowest ratio for the pressure-boundary materials, excluding bolting materials, of which the vessel is constructed.

c) The test pressure is the pressure to be applied at the top of the vessel during the test. This pressure plus hydrostatic head is used in the applicable design equations to check the vessel under test conditions, see Part 4, paragraph 4.1.6.2.a.

d) The requirement of paragraph 8.2.1.a represents the minimum required hydrostatic test pressure. The upper limits of the test pressure shall be determined using the method in paragraph 4.1.6.2.a. Any intermediate value of pressure may be used.

e) A hydrostatic test based on a calculated pressure may be used by agreement between the user and the Manufacturer. The hydrostatic test pressure at the top of the vessel shall be the minimum of the test pressures calculated by multiplying the basis for the calculated test pressure for each pressure element by 1.43 and reducing this value by the hydrostatic head on that element. The basis for this calculated test pressure is the highest permissible internal pressure, as determined by the design equations, for each element of the vessel using the nominal thicknesses, including corrosion allowance, and the allowable stress values given in Part 3, Annex 3.A for the temperature of the test. When this pressure is used, it shall be as set forth in the Manufacturer's Design Report.

8.6 Nomenclature

MAWP = maximum allowable working pressure

P_T = minimum test pressure

S = allowable stress from Annex 3.A. evaluated at the design temperature

S_T = allowable stress from Annex 3.A evaluated at the test temperature

Thanks for your reply.

but my question was ref to the GOST rules.

we required the allowable stresses in hydrotest condition as per GOST.

do you have experience with russian code?

thank you for your help

Best Regards

gmgm

Sorry, I don't have any information about GOST.

Hmm; there seem to have been some Code updates since I worked in this sector. I hope my first response doesn't lead anyone astray (even if it wouldn't be by far.)

Can't the Engineer/Surveyor for the organisation that is supplying burst/collapse indemnity insurance on the equipment help out over the 'phone?

How strange.