Manufacturing of Elbows 1

[sree60]

Hi members

In one of our offshore projects while reviewing the material test certificates for 10 In Sch 40 90 deg elbows ( 9.27 mm) we have found from supporting documentation that the raw material for these elbows is 6in Sch 80 ( wall thk 11.1 mm)pipes. we have doubt on genuineness of the material since how the diameter can be increased from 6 in to 10 in while forming.Can someone dirct me to some info on the manufacturing methods of elbows from pipes.
Thanks in advance
sree60

 

[MikeHalloran]

I know a couple of ways to make elbows, but I'm having a hard time figuring that one out...



Mike Halloran
Pembroke Pines, FL, USA

 

[unclesyd]

I don't know if they will give you any information but here is a company that fabricates fittings from pipe and such. The are/were know for quality fittings.

http://www.formweldfitting.com/1.html

 

[Mr168]

Have you actually checked the material yet? I've seen comparable things done by spin forming material and induction bending, but I'd still be suspect given that there's only .067" of playing room.

 

[ijzer]

The elbow could have been made by hot pressing it over a die. This is a quit common method.

 

[MikeHalloran]

Hot pressing sheet or plate, I understand.

The question was, how do start with 6" PIPE and end up with a 10" pipe elbow?



Mike Halloran
Pembroke Pines, FL, USA

 

[PAN]

Is this seamless pipe/elbow?
What is the pipe material?
What are the reference standards?
It is not common method for me. Did you ask the vendor to clarify?

 

[weeeds]

What part of the world were these fittings made in as per the Material Test Report?
We have been experiencing problems with validity of Test Reports from some parts of the world.

 

[PAN]

weeds,

I concur with you about the problems with validity of test reports. However, there are problems around the world...

It seems that the current market is for vendors and manufacturers. The purchasers have less power to ask for clarification in detail from vendors or manufacturers.

This is only my opinion...Good vendors and manufactures may be still available in this world...

Back to the case of sree60, the elbow manufacture should be the one who reply to his specific question...

Normally, I would not accept the material which is in doubt for the quality control record...

 

[BUTCHCWIQAM]

I have had the supplier give us MTR that match heat # but parts do not match. I have rejected material because of doubts like this. Have your inspectors be more vigilant when inspecting incoming material. And if it is already in the system you could use a Positive Material Identification to ease any concerns...If you don’t get what you need then cut off the supplier, I bet that there is someone else ready to take their place supplying material to you, if they don’t give you what you want.

PAN (Mechanical)“It seems that the current market is for vendors and manufacturers. The purchasers have less power to ask for clarification in detail from vendors or manufacturers.”

This happens when we give up, do not accept crap, and make them be responsible for the things they sell to the client… REJECT everything you have from this vendor if you feel that one piece is not correct… this is your gut talking to you or you would not have posted your concerns

 

[fredcsg]

The increase of the OD from 6" to 10" is usually done with a process called pipe expansion from 6 to 10 via a mandral. However you concern is the original pipe certification for the conversion of the seamless pipe to the seamless elbow. All fitting manufacturers should be able to provide you with the batch details which includes the original source of pipes (including the mill certificates).

 

[MikeHalloran]

Wow; who was that masked man(drel)?



Mike Halloran
Pembroke Pines, FL, USA

 

[fredcsg]

Thanks for the correction.