Det Norske Veritas - Germanischer Lloyd

NON-INTRUSIVE INSPECTION
 N DNV-RP-G103

Annotation

This recommended practice is primarily intended for those with responsibilities in the planning, implementation and acceptance of vessel inspections. It is aimed at the inspection of welded vessels constructed from metals, and related items, fittings and connections associated with them. The document is equally applicable to forged/spun metal pressure vessels, which contain no welds, as well as storage tanks and large diameter pipelines.

Although not intended to be covered by this document, some aspects of this recommended practice may also be applicable to vessels manufactured from other materials and plant items other than pressurised equipment, in which case some of the general principles developed may well still apply. The recommended practice provides guidance for:

1) determining when NII is appropriate in principle as an alternative to IVI or as a means of deferment of IVI

2) information requirements to plan for NII

3) defining the requirements for the NII method(s) to be selected

4) selecting methods that meet the requirements

5) evaluating the results of the inspection

6) documentation requirements.

The scope is limited by the following constraints.

— It is assumed that the date of the next inspection following NII will be determined in the same way as with any other inspection, based on sound engineering judgement and an understanding of the degradation rates and tolerance of the equipment to degradation. This recommended practice therefore makes no attempt to influence the timing of the next inspection, other than where the intended scope of the NII inspection has not been fully met or where it is used in support of deferment of a comprehensive inspection.