NDTnet 1998 Aug, Vol.3 No.8

Abstract

Eddy current flaw detector VD-89NM provides high speed inspection of gas pipeline surfaces with block of probes.It's a handle operated device for using by one operator. Power supply is provided by batteries inside.It detects stress-corrossion cracks under insolation coating up to 5mm thick and reduces inspection cost.

The inspection is earring out mainly for defects being detected earlier with in-pipe means using X-ray or ultrasonic method.VD-89NM realizes two parameters eddy current method of NDT, and allows to evaluate independently both gaps and crack depths in millimeters. Before inspection it must be adjusted on reference blocks.Inspection results are continuously presented on LC display. They could be stored in memory, checked by operator and saved in a standard IBM computer after inspection.DOS and WINDOWS compatible softwear allows documentation of results. It displays gaps and crack depths in millimeters, all diagrammes, plans of crack positions, 3D images of cracks on the pipe surface.It formes all necessary parameters, which may be used to evaluate gas pipeline survival time with special certificated means.

In 1995-1996 yr. VD-89NM was used for gas pipeline inspection in RUSSIA. Firstly that pipeline had been inspected by in-pipe ultrasonic inspection device "UltraScan CD" from "Pipetronix" company.

VD-89NM inspection allowed to get gas pipeline in use immediately by fast identification, confirming and subdividing all defects of pipeline surfaces with their crack depths profiles. Actually it makes inspection results more precise in concerning of pipe using posibility evaluation. All parts of pipe being not very dangerouse were leaved in pipeline.All rest results of inspection correspond to the same one detected by "UltraScan" flaw detector.

Computerized VD-89NM flaw detector using experience allowed to collect information bank on stress-corrossion defects in gas pipelines. Moreover, it gives an opportunity to study stress-corrossion cracks development process.

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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