Electro-Fusion Joint Failure Polyethylene Pipes Analysis and its Simulation using Finite Element Analysis
Electro – Fusion (EF) joint is a technique to join Polyethylene pipes (PE) pipes which carry gas or water medium.
Generally it is assumed that the PE pipe has a 50 year life. But PE pipes get failed before its natural lifetime due to
environmental load and conditions. PE joining is unavoidable in PE gas distribution pipe network. Failure of EF joint is a
fundamental reason for the decrease in service life. This paper includes principles of Electro-fusion joint, temperature
distribution, stress distribution due to thermal and structural loading. Due to this loading condition, inner cold region of EF
joint has highly stress concentrated area. This paper analyzed using finite element analysis and found that the inner pressure
causes to increase the gap between pipe and fitting while thermal load and external pressure tries to counteract the peeling
effect. Due to this peeling effect, inner cold region acts as a crack initiation region. Weld joint strength depends upon the
procedure adopted during EF joint which includes heating – cooling cycle, scrapping and contamination on joining surface
are significant for the strength and life of the joint.