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Re: [MW:14584] Advantage of Internal & External Clamps

By Materials & Welding


On Mon, 18 Jun 2012 11:24:53 +0530 wrote
>Dear experts

Hi,

External Clamps are allowed only for Tie-In joints or for short pipelines ans small diameter (<6 in.)

At least 50% of root pass is to be completed before the external clamp is released,
Internal alignment clamps are preferred for better alignment and not released until 100% of the root pass is complete.

Misalignment between the internal surfaces shall not exceed the lesser of 3mm or 1% of the pipe internal diameter at any point, more restrictions are set for Pipelines subject to strain.


Regards,
Manpreet Singh

what are advatages and disadvantages of using external clamps&

Internal clamps in Pipeline.



We'r doing 30"pipe line projects and client insist us to use only

Internal clamps for fitup pupose.



regards,

mohd



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