Sensitive Leak Test Pressure in ASME B31.3

[onrush]

Dear Members,

Regarding Sensitive Leak Test,

ASME B31.3 para.345.8 (a) describes that "The test pressure shall be at least the lesser of 15 psi gage
or 25% of the design pressure."
It means that maximum required test pressure is 15 psi.

However, para.345.8 (b) describes that "The pressure shall be gradually increased until gage pressure
the lesser of one-half the test pressure or 25 psi is attained........"

If maximum required test pressure is 15 psi as per para.345.8 (a), how can we increase test pressure
up to 25 psi as per para.345.8 (b)?

In my opinion, we should recognize "at least" in para.345.8 (a), which means that this paragraph
defines only minimum requirement. It also means that we may use the test pressure above 15 psi.
That's why para.345.8 (b) mentions 25 psi.

Am I correct?

 

[stanweld]

The minimum test pressure mandated by B31.3 is the lesser of 15 psi or 25% of the design pressure (when design pressure is less than 60 psi). The test pressure can always be greater than the minimum required by Code.