Pipe Pressure per ASME B31.3 (304.1.2)

Written by Jerry Ratzlaff. Posted in Pipe

The pressure rating of comparable pipe material to fitting material.

formula

\(\; p = \frac { 2tSQW }     { d \;-\; 2ty } \)

Where:

\(p\) = pressure rating

\(t \) = pipe wall thickness

\(S\) = allowable stress

\(W \) = weld joint strength reduction factor ASME B31.3 Para. 302.3.5(e) (Typically = 1.0)

\(Q \) = quality factor

\(d_o\) = outside pipe diameter

\(y\) = ASME B31.3, Table 304.1

Solve for:

\(t = \frac { pd }     { 2 \left( SQW \;+\; py \right) } \;\)

formula y

\(\; y = \frac { d_o \;+\;2c }     { d_o \;+\; d_i \;+\; 2c } \)

Where:

\(y\) = ASME B31.3, Table 304.1

\(d_o\) = outside pipe diameter

\(d_i\) = inside pipe diameter

\(c\) = Sum of mechanical allowances plus corrosion and erosion allowances