Talk about the structure and heating technology of the trolley-type annealing furnace

The fuel of the trolley annealing furnace is also following the development of fuel resources and the progress of fuel conversion technology, and the selection of solid fuels such as lump coal, coke, and pulverized coal is gradually switched to furnace gas, city gas, natural gas, diesel, and fuel oil. Wait for gas and liquid fuels, and develop a variety of combustion equipment compatible with the fuel used. The structure, heating technology, temperature control and furnace atmosphere of the trolley-type annealing furnace will directly affect the production quality after processing. In the casting heating furnace, increasing the heating temperature of the metal can reduce the deformation resistance, but excessively high temperature will cause grain growth, oxidation or overburning, which will severely affect the quality of the workpiece. In the heat treatment process, if the steel is heated to a certain point above the critical temperature and then suddenly cooled, the hardness and strength of the steel can be improved; if the steel is slowly cooled after being heated to a certain point below the critical temperature, the steel can be The hardness drops and the toughness improves. In order to obtain workpieces with precise dimensions and bright surfaces, or to reduce metal oxidation to reach maintenance molds, reduce machining allowances, etc., various low-oxidation heating furnaces can be used. In an open-flame heating furnace with less oxidation and no oxidation, the incomplete combustion of the applied fuel produces restorative gas, in which heating the workpiece can reduce the oxidation burn rate to below 0.3%. The controllable atmosphere furnace is the use of artificially prepared atmosphere, which can stop gas carburizing, carbonitriding, bright quenching, normalizing, annealing and other heat treatments: to achieve the purpose of changing the metallographic layout and improving the mechanical properties of the workpiece . In the movable particle furnace, the burning gas of fuel or other fluidizing agent applied externally is forced to flow through the graphite particles or other lazy particle layer on the hearth. The workpiece can be buried in the particle layer to complete the intensified heating, or it can be stopped. Various non-oxidizing heating such as carburizing and nitriding.

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