Hello Akber,

The loadings that occur at anchors, supports, hangers and any other piping system restraints MUST be calculated and they MUST be addressed by the system design. This loading is one of the "Design Conditions" that the Code requires the design to address.

Of course, if the design can control the displacement close to the point where the the pressure impinges upon the pipe wall, it may be possible to prevent a large moment at a more remote point like an anchor.

The PD / 4t term ONLY addresses the longitudinal tensile stresses in the pipe wall as a result of the longitudinal pressure (bore thrust). It does not address bending moments (and their stresses) caused by any pressure related displacement. The stresses caused by bending moments are addressed AT THE POINT WHERE THEY OCCUR by the second term in the "sustained stress" equation: iM / Z).

Regards, John.