Different thickness between pipe and Tee

[farzam]

Dear All,
I have a question regarding pipeline with pigging system. The pipe thickness is caculated is lower than the thickness of equal Tee(half percent) For pigging the ID of pipe and Tee should be same, normally whats the solution? I guess increasing thickness of pipe(same as Tee) is not good one.
Please let me know your opinion

Thanks in Advance

 

[pennpiper]

Farzam,
Please do not try to "over-engineer" something that has been working just fine for a hundred years or more.

 

[MJCronin]

shazam.....

Some companies offer "flexable" or gell pigs...

All piping wall thicknesses are not the same, even though the pipe schedule is...

We are not building a precision watch here....

-MJC

 

[zdas04]

All cleaning or batching pigs can handle a pretty wide variation in wall thickness. I once built a 20-inch line that used 6 different wall thickness of pipe (pipe was in short supply and I bought the odd lots that were in people's yards) with a pretty wide variation in ID. We've been running turbo pigs in this line 1-2 times per week for 12 years with no problems at all.

I've also seen a 12-inch foam pig make it through a 3-inch vent (not in reusable condition, but without too many pieces missing).

If you are running a smart pig it is always best to run a dummy pig first to see if the smart pig will get stuck. It is amazing how much variation even something that delicate can tolerate. You didn't say what size line you are working with, but 0.5% variation in 10 inch is 0.05 inches. In 36 inch it is 0.18 inches. Neither number should be a problem.

David

 

[BigInch]

If you can weld the two wall thicknesses directly together and still be within the wall thickness difference allowed by code, then don't worry about pigs passing the weld points.

If you can't weld the pipe and fitting directly, then you need a transition piece, so don't worry about it in either case.

"Make everything as simple as possible, but not simpler." - Albert Einstein (1879-1955)
***************

http://virtualpipeline.spaces.live.com/

 

[farzam]

Dear David and BigInch,

Thanks a lot for your recommendations
Farzam

 

[c1defence]

Specify the Tee to be fabricated with the same ID as the pipe. Thickness of pipe and tee will not need to be the same as different design method and materials are used.

 

[JohnBreen]

...........I hope it is a barred Tee

 

[Zziggiz]

If you working under API code, it tells you the tollerances inc ovality, buckles and etc.
That is why you use gauge plate after hydro test. I think difference in diameter up to 5% of inside pipeline dia is acceptable so your is 0.5% that looks ok.