Session: CS-22-01 Repair and Replacement Activities to Maintain Component Integrity

Paper Number: 106845

106845 - Study on Molten Zone of Butt Fusion Welding Process With Phased Array Ultrasonic Technology for Polyethylene Pipe 

Butt fusion welding is one of the main methods of connecting polyethylene pipes, widely used in the construction of large diameter thick wall pipes. However, the butt fusion joints are the weak link in the polyethylene pipeline. The butt fusion welding parameters such as the heating plate temperature, heating time and welding pressure affect the properties of welded joints. Previous studies have shown that the welded joint properties are related to the size and shape of the molten zone. The molten zone condition can be used to assess the welding process parameters for butt fusion welding. In this study, during the butt fusion welding, the changing state of the molten zone was recorded to obtain the optimal welding process parameters. The real-time video recording of the whole process for polyethylene butt fusion welding was proposed, using ultrasonic phased array focusing and imaging techniques. The ultrasonic signal was detected at the boundary of the molten zone based on the acoustic impedance contrast between the molten and unmolten zones. According to the change of boundary ultrasonic signal, the changing state in the shape and size of the molten zone was recorded and compared in real time. This experimental method is provided to evaluate the welding process parameters for polyethylene butt fusion welding.

Presenting Author: Yangji Tao Zhejiang Academy of Special Equipment Science

Presenting Author Biography: master of Zhejiang University, working in Zhejiang Academy of Special Equipment Science, for the research of nondestructive inspection for pressure equipments.

Authors:

Yangji Tao Zhejiang Academy of Special Equipment Science
Weican Guo Zhejiang Academy of Special Equipment Science
Yan Shi Zhejiang Academy of Special Equipment Science
Cunjian Miao Zhejiang Academy of Special Equipment Science
Ping Tang Zhejiang Academy of Special Equipment Science