Reducing Fittings

While specifying reducers and reducing tees, sometimes we dont specify schedules for both the sizes. Bigger size schedule is normally specified even if small size has a different schedule.

What is the reason for that? Is there any limitation for that? How this schedule difference is taken care at fabrication stage?

While specifying reducers and reducing tees, sometimes we dont specify schedules for both the sizes. Bigger size schedule is normally specified even if small size has a different schedule.

What is the reason for that? Is there any limitation for that? How this schedule difference is taken care at fabrication stage?

Why don't you specify schedules ? If you don't, how could you get them purchased and used correctly ?

The schedules of the fittings match those of the pipes or connecting fittings, so the fabricator has no problem.

I am talking about a common practise followed in many companies. They dont specify both the scedules. I am not clear what is the philosophy behind that. May be they are ensuring that thickness difference is within limits specified by B16.25

Not crystal clear yet. Does anybody know why?

I don't think that is a common practise simply because it not right. One can not specify a reducing tee for reducer without specifying their schedules unless these are not butt weld fittings.

I am sure no one want to see a sch 160 pipe welded to a sch 40 fitting in a sch 160 system. And if that is wrong, then the "common practise" must be wrong.

I have seen it in many specs. If we dont know the thing then we should not assume that its not there.

I think the specs already specified the pipe schedules, and the specs assume that the piping engineers know his job well enough to specify the schedules of the fittings.