NDTnet 1998 Aug, Vol.3 No.8

Full-Text - Abstract

The very high requirements for internal surface quality of welds can only be met if strict welding procedures are followed and the welds intensively checked. As key requirements are internal cleanliness, smooth geometry, absence of weld defects such as crater pores, and very low heat tint levels, only visual inspection can verify that the requirements are met. Especially the heat tint evaluation is a task for skilled and experienced inspectors. In Denmark, the references for the requirements and the visual inspection are, usually, The FORCE Institute "Reference charts", report 94.30 and 94.34 (English version), to obtain optimal corrosion resistance without post weld treatment. In small diameter pipes, visual inspection can only be made with small videocameras or videoendoscopes. The characteristics and the positive and negative aspects of these two types of equipment are discussed.

The requirements of the Danish pharmaceutical industry for primary systems are weld quality B ace. to EN 25817, no internal weld defects, heat tint level max. C, ace. to FORCE Institute report 94.30/94.34.

Depending on the priority of the system, different inspection extents are prescribed even up to 100 percent. The inspection can be made either by the Q/A Dept. of the company doing the welding or by a third party inspection company. Videotapes traceable to each weld are part of the documentation for the plant.

Abstract Source:
Book of Abstracts, 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN: 87-986898-0-00

Full-Text Source:
Proceedings of the 7th European Conference on Non-Destructive Testing, 26-29 May 1998, ISBN:

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