Philippe Vanspeybroeck

Holographic investigation of brittle crack propagation in plastic pipes

Abstract Plastic pipes dominated the low pressure gas distribution piping market during the last decade. Research on steel pipes has long since indicated that the susceptibility to rapid crack propagation (RCP) increases with increasing diameter. Although most plastic pipes used in gas distribution systems are of small diameter (

Holographic NDT methods for plastic pipe vibration and brittle crack propagation analysis

Plastic pipes are frequently used for low pressure gas and water distribution. One of the main problems with their wide commercial applications is rapid crack propagation (RCP). This results in enormous losses of energy resources and environment pollution. Recent incidents show that it is of importance to find criteria to assess the safety conditions for large diameter piping before its installation. In this report some results of holographic non-destructive testing of plastic pipes are presented. Double-pulse holographic interferometry measurements of stress distribution at small scale steady state (S4) tests for 3 - 5 bar pressurized plastic pipes with (phi) 110 mm to 200 mm were performed. Also the mechanically induced vibration modes of non-pressurized (phi) 200 mm plastic pipe were visualized with the purpose to check stress distribution.

Nondestructive study of plastic pipe characteristics with double-pulse holographic interferometry

In this paper we present the results of analytical study and experimental examination of long pipe oscillations. Two different approaches have been used for theoretical study, which are the Global Modal Analysis and direct solution of the wave equation for oscillating modes revealing and analysis of the displacement. The obtained results are compared with experimental data from pulse-laser holographic non-destructive testing of pipe vibration.

Holographic interferometry for polymer pipes vibration analysis

In this paper we present the results of analytical examination of long pipe oscillations. The study performed the characteristics of the oscillations, based on solution of a system of the wave equations for surface displacement. The pipe under the consideration is an elastic cylindrical shell. The oscillations are initiated by an externally applied loading force, that has a form of short-acting pulse. The results obtained are compared with experimental data from interferometric analysis of a 6m long polymer pipe. Keywords: holographic non-destructive testing, oscillation analysis.