Thermoelastic state during electrofusion welding of polyethylene pipes at different ambient temperatures

Abstract

Abstract The problem of welding polyethylene pipes used in the mining industry at low ambient temperatures is considered The numerical solution of a thermoelastic problem revealed the distinctive features of thermal and stress-strain states of weld connections of polyethylene pipes using embedded heater couplings at different ambient temperatures. It is found that in low-temperature conditions, the size of the melted zone is considerably smaller than during welding at permissible temperatures. In this regard, the pressure insufficient for high-quality welding is created between the coupling and the pipe. It is also shown that at the time of melt crystallization, the maximum values of stresses and strains during welding at low temperatures are higher than during welding in the permissible temperature range, which causes high values of residual stresses. The results obtained can be used in the development of low temperature welding technology.