Energy-saving type roller hearth continuous bright normalizing annealing furnace

Abstract

An energy-saving type roller hearth continuous bright normalizing annealing furnace comprises a heating chamber (1), a heat preservation chamber (2), a furnace roller (3), a flue (4) and a waste heat recovery section (5). A waste heat recovery boiler (6) is arranged on the furnace wall of the waste heat recovery section (5), the flue (4) is arranged at the tail end of the waste heat recovery boiler (6), and a smoke tube is installed in the waste heat recovery boiler (6); a steel tube which is subjected to waste heat utilization by means of the waste heat recovery boiler (6) on waste heat recovery section (5) is discharged from the boiler, and cooled in the air, and the tapping temperature of the steel tube can be controlled around 250 DEG C; and simultaneously, high temperature smoke in the heating chamber (1) and the heat preservation chamber (2) is subjected to waste heat utilization by means of the smoke tube in the waste heat recovery boiler (6) and discharged from the flue (4) at the tail end of the waste heat recovery boiler (6). According to the energy-saving type roller hearth continuous bright normalizing annealing furnace, the waste heat recovery boiler can simultaneously exchange high temperature smoke heat energy and radiant heat energy of the steel tube to produce steam which is used for steel tube production and ordinary life; and besides, the tapping temperature of the steel tube is reduced so that secondary oxidation burning loss is reduced and qualities of outer surfaces of products are improved.

Description

technical field [0001] The invention relates to a heat treatment furnace, in particular to an energy-saving roller bottom continuous bright normal annealing furnace. Background technique [0002] Existing products such as steel pipe, steel plate and strip steel, the structure of the roller bottom continuous normal annealing furnace used in the production process is shown in the attached figure 1 , 2 As shown, it includes a heating chamber 1, a heat preservation chamber 2 and a furnace roller 3, the heating chamber 1 is connected to the heat preservation chamber 2, and the furnace roller 3 is installed in the heating chamber 1 and the heat preservation chamber 2 through the bearing seat 31 outside the furnace wall 32, and the furnace Above the wall 32 is a furnace roof 33, below is a furnace bottom 34, and a flue 4 is arranged at the tail end of the heat preservation chamber 2. In the roller hearth continuous annealing furnace, steel pipes, steel plates, and strip steel pro...

AI Technical Summary

Problems solved by technology

Its disadvantages are: the temperature of steel pipes, steel plates and strip steel products directly out of the furnace after annealing or normalizing is as high as 800°C, resulting in a large amount of high-temperature heat energy being released in the atmosphere, resulting in poor working conditions for annealing workers; at the same time, When products such as steel pipes, steel plates, and strip steel are annealed at about 800°C and air-cooled, the iron in the surface layer will chemically react with oxidizing gases (such as oxygen and water vapor) in the air to produce secondary oxidation. After the secondary oxidation of products such as steel plates, steel strips, etc., a thick layer of secondary oxide scale is formed on the surface, which affects the pickling speed of steel pipes, steel plates, and strip steel products, and increases the consumption of sulfuric acid during pickling; if When the finished steel pipe, steel plate and strip steel are annealed, the secondary oxide scale is thicker, which will not only cause the loss of steel, but also reduce the outer surface quality of steel pipe, steel plate and strip steel.

[0003] In addition, most of the high-temperature flue gas in the annealing furnace in the prior art uses an air heat exchanger for waste heat utilization, but the heat exchange effect of the air heat exchanger is poor, and it can only reduce the high-temperature flue gas at about 750°C to 500°C. ℃, there is still a large amount of heat energy in the flue gas that has not been fully utilized, and steel pipes, steel plates, and strip steel products need steam heating in the production process, and it takes a lot of energy to generate steam through coal (gas) boilers. Energy, which is not conducive to enterprises to reduce production costs and wastes national energy resources, but also causes environmental pollution and deteriorates the working conditions of workers

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