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ansi welding end preparation a
hello all!!
as you know ansi b16.25 states the end preparation necessary when welding pipes depending on the thickness and the use or not of backing rings. my problem is that i have been proposed by a supplier to weld my pipes without using backing ring but with the end preparation reccomended by ansi b16.25 when those rings are used.
i know it sounds a bit strange because the end preparation proposed seems to be more complicated than the one required by ansi when not using backing ring.
should i approve this end preparation? i was going to refuse it but i am not sure if there are reasons for change it or if the end preparation for backing rings is valid as well when not using them.
thank you for any help.
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the question you need to ask is can the fabricator get an acceptable weld using his end preperation.
if you accept his end preperation don't let him get ahead of the inspection process verifying that he is producing acceptable welds. if you don't feel compfortable i would increase the inspection rate initially. make sure you inspect all welders initially.
we at one time required a land on all groove welds, especially in stainless steel until the welders demostrated that the could make an acceptable weld using feather edging and later walking the cup.
a little secret, not all welders can make an accptable weld with backing rings. we had a lot trouble at times and i had to make a lot of calls on welds.

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借用达朗贝尔的名言：前进吧，你会得到信心!
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