Keyword: «cooling rate»

In this paper, a study of structural transformations of 14G2SAF pipe steel during welding, changes in its strength and ductility characteristics when simulating real thermal cycles under different ambient temperature conditions is carried out. The most optimal intervals of cooling rates were selected experimentally.

Existing technologies for welding polyethylene pipes with embedded heaters allow welding in the ambient air temperature range from -10℃ to 40℃. In this article presents the results of the implementation of the technology developed at the Institute of Oil and Gas Research, Siberian Branch of the Russian Academy of Sciences, which makes it possible to weld polyethylene pipes using fittings with embedded heaters in an extended range of ambient temperatures from -50℃ to 40℃. A description is given of a prototype of a welding machine that allows welding for an extended temperature range. Using the developed software, the device performs the operations of preheating, temperature equalization, reflow and controlled cooling in automatic mode. A description of the technical implementation of the prototype welding machine for low temperatures is given and some test results of specimens welded by the prototype at low temperatures are shown.