In modern industrial production, heat treatment has become an extremely important process measure to ensure product quality, improve processing conditions, and save energy and materials. At present, about 80% of the parts on various machine tools require heat treatment. As for cutting tools, cutting tool measuring tools, mold bearings, etc., Brazing requirements for carbide woodworking tools almost 100% require heat treatment. Because the role of heat treatment process in production engineering cannot be ignored, and any heat treatment process is realized in corresponding heat treatment equipment. Among the main heat treatment equipment, the heat treatment furnace is the most important equipment. Debinding and sintering of metal injection molding components The research object of this paper is a pit-type resistance furnace that uses electric energy to heat raw materials, also called a pit-type furnace. Mainly used for heating long workpieces: such as automobile bearings, ship turbines, power plant generator spindles, etc., which are important equipment components related to national economic production. In the past, the control of pit furnaces generally used temperature instruments to display the temperature, and the temperature was adjusted by manually operating gas ignition. Effect of filler metal on vacuum brazing of cemented carbide and steel The control was not flexible enough, so the quality of the heat-treated workpieces was not high. It cannot well meet the needs of practical applications. This article is aimed at this shortcoming and uses PLC to transform an old-fashioned pit furnace temperature control equipment to achieve PLC control.Heat treatment process for wide and thick plates