Abstract
Results of investigation of the effect of the temperature of the surrounding air on the dynamics of the temperature field in socket welding of polyester and pipes are presented. It is shown that in order to ensure the permissible dynamics of the temperature field at the air temperature below standard temperatures, it is necessary to preheat the socket prior to welding together with the welded sections of the pipes, and the welded joint should be cooled under a layer of heat-insulating material.