Plastic pipes used to transport gas and water have to be tested to stringent standards. One test involves pressurising samples of the pipe for long periods at elevated temperatures, during which it should not fail. Another test continuously increases the pressure till the sample fails. Production samples are prepared for these tests by cutting external longitudinal notches, of defined dimensions, in the wall of the pipe. These notches, four of which are spaced around the circumference, act as stress concentrators and represent far in excess of any possible accidental damage to the pipe whilst it is being laid.A machine has been jointly developed by Quercus Computer Systems and a precision engineering company, which automatically cuts the test notches in samples of pipe. The operator merely has to input the dimensions of the test sample, it's wall thickness and the type of test to be carried out. The computer calculates the required machine movements, based on stored test specifications, to produce the required length and depth of notch for the particular test.
These machines were in use at several locations in the UK, and also in Sweden, Portugal and India.