NDTnet 1998 Aug, Vol.3 No.8

Abstract

The economical result of plants in chemical and petrochemical industry is strongly dependent on the reliability of all components and on an undisturbed production process. But not only economical points of view are important. Other aspects like safety of plants, environmental protection and governmental regulations have to be considered. Following these requirements the importance of regular surveillance and planned maintenance is growing more and more.

The presented report discusses some special NDT-methods for the area of inspection, their practical performance and experiences as tools for a planned surveillance and maintenance for such production plants.

One discussed method is projection radiography for thickness measurement of isolated pipes in connection with a computer program for checking and storage of measuring results and visualisation of pipeline systems by a CAD-program.

The first step of application is the definition of the special measuring locations within a complex pipe system. Once these points are defined the isometric drawing of the system is developed by the CAD program. All defined surveying points are marked in the isometric drawing. The CAD program is directly linked to a database program (MS Access) so that by mouseclick on the marked measuring point in the CAD drawing immediately all result for this special point can be seen. The wall thickness measurements are done by radiographic projection exposures so that the pipe isolation must not be removed. Many statistical evaluations about the condition of the whole pipe system may easily performed after some initial measuring periods.

The other method is based on radiometric measurement of the density profile of destillation columns and similar components. By this method too the inspection can be done without removal of the outer isolation and even without stopping the process. If process irregularities are observed the internal structure of the components can be inspected and damages in the internal structure as well as the area of damage can be recognised and located so that a rapid repair is possible. Examples show the effectiveness of this method.

The methods and the given examples shall show how the required inspection and surveying costs may be reduced to a level as low as possible.

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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