Numerical analysis of the heat transfer and fluid flow in the butt-fusion welding process

• Published in: Korea-Australia rheology journal Vol. 29; no. 1; pp. 37 - 49
• Main Authors: Yoo, Jae Hyun, Choi, Sunwoong, Nam, Jaewook, Ahn, Kyung Hyun, Oh, Ju Seok
• Format: Journal Article
• Language: English
• Published: Seoul / Melbourne Korean Society of Rheology, Australian Society of Rheology 01.02.2017; Springer Nature B.V; 한국유변학회
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Complex Fluids and Microfluidics; Food Science; Heat transfer; Materials Science; Mechanical Engineering; Polymer Sciences; Soft and Granular Matter; Thermal expansion; 공학일반; polymer processing; butt-fusion welding; finite element method; computational fluid dynamics; heat transfer
• ISSN: 1226-119X; 2093-7660
• DOI: 10.1007/s13367-017-0005-3

Butt-fusion welding is an effective process for welding polymeric pipes. The process can be simplified into two stages. In heat soak stage, the pipe is heated using a hot plate contacted with one end of the pipe. In jointing stage, a pair of heated pipes is compressed against one another so that the melt regions become welded. In previous works, the jointing stage that is highly related to the welding quality was neglected. However, in this study, a finite element simulation is conducted including the jointing stage. The heat and momentum transfer are considered altogether. A new numerical scheme to describe the melt flow and pipe deformation for the butt-fusion welding process is introduced. High density polyethylene (HDPE) is used for the material. Flow via thermal expansion of the heat soak stage, and squeezing and fountain flow of the jointing stage are well reproduced. It is also observed that curling beads are formed and encounter the pipe body. The unique contribution of this study is its capability of directly observing the flow behaviors that occur during the jointing stage and relating them to welding quality.