Pipe schedule for Socketweld Flange

you only need to specify the rating of the flange. Because in case of socket weld flange only the outer dia of the pipe is important, which is constant.

SB

Shujabutt,

Your answer is correct for Slip-On Flanges but is not correct for Socket-Weld Flanges or Weld Neck Flanges.

The Socket-Weld flanges and Weld Neck Flanges have an "ID" that needs to be consistent with the "ID" of the pipe

Ideally we should specify pipe schedule with all type of flanges, particularly with weld neck, socket weld and lap joint flanges. For socket joints coupler (Socket) ID should be equale to pipe ID, otherwise extra pressure drop and the turbulance in flow will be there.

OP is referring to socket weld only second post is the correct response unless I am missing something.