Ultrasonic testing standard of fusion joint for polythylene(PE) pipeline

The polyethylene(PE) pipes are widely used to transport city gas worldwide with steel pipes. Generally, Steel pipe are used for high pressure line and PE pipe for low pressure line whose pressure is less than 4 kg/m2. The steel pipe line are subject to 100 percent Radiographic Testing(RT) during installation stage, on the contrary, there has been no the established testing method for the welding fusion joint of polyethylene pipes, so all quality control is limited only Visual Testing(VT) or management of Fusion welding equipment. Even though PE pipeline is exposed to lower pressure than steel pipeline, the gas leakage from PE pipe may result in almost the same serious consequence from steel pipeline. So, it is necessary to develop the reliable testing standard for PE pipeline from the point of view of NDT engineers.