Service reliability of sections of an electric resistance heater in the local heat treatment of circumferential welded joints in pressure vessels

摘要

A method of evaluating the service reliability of heating elements of the sections of the electric resistance heater with different forms of the surface, situated inside or outside the vessel, is proposed. The design of the sections of the heater is taken into account by a correction coefficient characterising the ratio of the areas of the heating and general surfaces of the sections.The criterion for the service reliability is the temperature of the emitting surface of the elements of the section.The values of the temperature, determined using the proposed procedure, are higher than the calculated values of the temperature published in the scientific and technical literature (by up to 150 deg C).