Problem:

How to calculate the allowable stress for hydrotest case?

Solution:

Refer below references for calculation of allowable stress in hydrotest condition,

1. According to ASME Section VIII Div. 2, Clause 4.1.6.2,

Allowable stress = 95 % of yield strength

2. According to ASME Section VIII Div. 1,

Generally allowable stress = 90 % of yield strength.

Note that 90 % yield limit is not given in code but it is common praxis.

If you want to change the allowable stress at hydrotest pressure case please follow below steps,

Step-1: Select user defined safety factors from Vessel Properties<Design Conditions<Design Values<User Defined<Edit

Step-2: Change C4 % value to desired one. You will get required safety factor.