If dish end spin hole is closed by 100mm dia plate- same grade/thk (Full penetration Butt Weld) does it require RT? (vessel is coded, RT-1) is it a catogorised joint?

Yes. See UW-34.

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Konrad Anikiel

Refer the clause of UW 34.

This weld is a butt weld, but it is not categorized. It
shall not be considered in establishing the joint efficiency
of any part of the head or of the head-to-shell weld.

Hence it is upto interpretation whether RT is must or not. Also in my opinion, since it is flattened spot then verification as per UG 32 (o) is advisable.

If the spin holes closed by a plate of 100mm diameter-is it required RT?

It doesn't matter. The only difference is that you can close this hole without using any plug when it's under 60mm. Your 100mm hole has to be closed with a piece of plate or other form of a plug.

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Konrad Anikiel

A spin-hole weld is a Cat. A weld in my opinion, and the RT will follow Table UW-12 according to the Joint Efficiency. For your RT-1 vessel, full RT is required for the spin hole weld. No doubt.

DK

Dirk,
UW-34 leaves no latitude: it is treated as a butt weld without category. When a requiremment pertains to butt welds or material thickness- it is applicable, when it refers to categories, it does not apply. Anyway, I can't imagine a simplier weld to have it radiographed. Sigle exposure, single film, right angle...

Original poster: Apologise for any confusion, I haven't asked what your requirement to perform the radiography is based on. I hope it's clear now.

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Konrad Anikiel

statement retracted.