Pipeline tie-in measurement

Date 11-08-2019 11:13

On a 36” pipeline, replacing a section 200 feet long. Cold cut & remove the old section, drop in the new section which is a bit longer than necessary, do one weld, then how exactly is the other end measured?

With a sideboom, overlap the new section on one side of the old pipe, make a mark.

Swing it over to the other side, make a mark.

Put it on top of the old pipe, make a mark.

Then take the shortest of those marks and that’s the final cut?

Or am I way off base here?

By Shane Feder (****)

Date 11-08-2019 21:35

You are responsible for a tie-in on a 36" pipeline and you are on here asking how to do it ?
How did you get your job if you have no prior experience ?

By atc250r (**)

Date 11-08-2019 21:51

Nope, not responsible for it. Just going to be a part of it and don’t want to look completely green.

By Shane Feder (****)

Date 11-08-2019 22:34

The pipe is placed beside and marked.
It is then moved away for cut to be performed.
Once preparation of ends is complete it is moved back in to place.
Final adjustment to achieve desired root gap is done by raising or lowering one or both pipes at a reasonable distance away from the tie-in point.
It has to be far enough away from the joint to not affect the vertical face of the two pipe ends
If sitting flat in a pipe trench with no possibility of lowering the same result can be achieved by moving the pipe/s sideways.
Hope that helps.

By atc250r (**)

Date 11-09-2019 15:24

Noodling is what we call that. Ok, I was under the assumption we’d do one weld before making the final cut, but maybe not. Thanks Shane

By Shane Feder (****)

Date 11-09-2019 22:48

You are correct - one weld is completed first.