Dears,

In a revamp work we have A691 1.25 Cr piping in process piping application having design temp of 550 C; Table 302.3.5 there now asks for weld joint strength reduction factor W, which was not there earlier in 2000 era.

As both existing piping and new portion forms an integral pressure integrity system, will different portions be designed for different editions of B31.3; otherwise, older portion of piping needs to be replaced by thicker piping designed by new edition of B31.3.

What should be the correct codal position; is B31.3 applicable for revamp job ?

regards,
sam