In February 2010 a European (FP7) funded project on the development and validation of an automated non-destructive evaluation (NDE) approach for testing welded joints in plastics pipes (TestPEP), involving 15 organisations from seven European countries, was started.
Plastics pipes offer significant advantages over other materials such as cast iron, steel, copper and concrete, for the transportation of fluids such as natural gas, water, effluent and corrosive liquids. They do not corrode; have a longer predicted service life, leading to less frequent replacement; they are less expensive to install due to their light weight and flexibility; and have significantly lower leakage rates due to having an all-welded system. However, their more widespread use is being restricted by the lack of a reliable NDE method for the welded joints. Pipeline leakage does not only cause high repair costs but can also result in disastrous environmental consequences.
The TestPEP project will develop phased array ultrasonic NDE procedures, techniques and equipment for the volumetric examination of welded joints in polyethylene (PE) and other plastics pipes of diameters up to 1m. In addition, the project will develop an automated inspection system that will be able to inspect pipe-to-pipe and pipe-to-fitting butt and socket joints in various plastic pipe materials and diameters between 90 and 1000mm.
A key aim of the project is to develop an inspection system that is site-rugged and simple to operate. Current phased array instruments require ventilation and space and many have fragile viewing screens. The concept in this project is to have a black box instrument with a simple ethernet connection to download the recorded data, and to provide the necessary robustness of the phased array probe. Another objective of the project is to analyse the data semi-automatically so that a red/green (yes/no) answer can be provided for the quality of the welds and the system can be operated by normal pipe laying technicians.
The prototype NDE equipment, designed and built as part of this project will be assessed under both laboratory and field conditions.