Pipeline Bends- Tangent Lengths

[JT100]

Could anyone please explain exactly what these are? I believe it is something to do with extra length for welding and it tends to have been approx 500mm whenever I've come across it however I am not 100% sure exactly what they are. Thanks. jt

 

[Sid7]

JT

For a 'pulled bend' you need some straight length at both the ends for the bending machine to get hold of the piece. In general this length is specified as 500mm, I believe.
regards

Siddharth
These are my personal views/opinions and not of my employer's.

 

[SJones]

ISO 15590-1 might also be a useful standard for you to peruse.

Tangent lengths are simply the straight sections at the end of the bend usually left on so that field cutting can occur to fit and weld the item into the system without encroaching upon the curved portion.

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[JT100]

Thanks to both above, cleared it up for me. jt

 

[BillBirch]

It is always useful to retain some of this straight length, rather than trimming back to the tangent line to ensure that there is not excessive ovality (due to the bending process) where you want to weld to the adjacent pipe.