Minimum Wall thickness requirement for Pipe per ASME B31.3

[Meck91]

Hi,

Is there any requirement specified in ASME B31.3, regarding pipe minimum wall thickness. Just like ASME Section VIII Div. 1 specify minimum requirment for plate thickness for pressure vessels, i thought there might be some clause in ASME B31.3 as well.

Thanks,

Meck91

 

[boo1]

ASME B31.3 for low pressure boilers. For power boilers use ASME B31.1
Paragraph 304:

t= PD/ 2[(SEW/I)+PY]

 

[XL83NL]

The minimum wall thickness is designed according para 304 of B31.3, and is a function of (amongst other) pressure.
You have to take into account the mill underrun tolerance per the purchase specification you're designing the piping system for.
This is included in the part of T > tm = t + c. Usually the tolerance is 12.5%, but it can be different.

 

[boo1]

304.1.2 Straight Pipe Under Internal Pressure
(a) For t < D/6

t= PD/ 2[(SEW/I)+PY]
or
t={P(d + 2c)}/{2[SEW − P(1 − Y)]}

b) For t ≥ D/6 or for P/SE > 0.385
Calculation of pressure design thickness for straight pipe requires special consideration of factors such as theory of failure, effects of fatigue, and thermal stress.