Vertical-type strip steel jet heat treatment device and method

Abstract

The invention relates to the field of continuous heat treatment of a cold rolled steel strip, particularly to a vertical-type strip steel heat treatment device and method. The vertical-type strip steel jet heat treatment device are provided with a pre-heating section, a heating section, a soaking section, a slow cooling section, a rapid cooling section, an overaging section and a final cooling section in sequence in a steel strip moving direction. The pre-heating section, the heating section, the soaking section, the slow cooling section, the rapid cooling section, the overaging section and the final cooling section are filled with protective gas, and heat exchange is directly performed between the steel strip and the protective gas. The protective gas in two adjacent sections is insulated with a hermetically-sealed device. According to the vertical-type strip steel heat treatment method, direct heat exchange between the steel strip and the protective gas is carried out all the time during a heat treatment process. According to the device and method, the steel strip is located in mixed protective gas all the time, residual heat from flue gas of radiant pipes is fully utilized, and rapid, uniform, efficient heating and cooling of the steel strip are achieved in a situation that the surface quality of the steel strip is ensured. Energy conservation and emission reduction is achieved, the length of a furnace is reduced, and the apparatus and method has bright popularization prospects in continuous annealing and hot galvanizing units.

Description

technical field [0001] The invention relates to the field of continuous heat treatment of cold-rolled strip steel, in particular to a vertical strip steel heat treatment device and method. Background technique [0002] At present, the medium and high-end cold-rolled strip products generally use vertical continuous annealing furnaces, and the atmosphere in the furnace is a mixed protective gas of N2 and H2. figure 1 It is a schematic diagram of an existing typical continuous heat treatment furnace. The heat treatment process section is mainly composed of preheating section 2, heating section 3, soaking section 4, slow cooling section 5, fast cooling section 6, overaging section 7, final cooling section 8, etc. from left to right according to the running direction of strip steel 1. . Among them, the preheating section has two methods of direct flame heating and flue gas preheating; the heating section basically adopts the radiant tube radiation heating method under the mixed...

AI Technical Summary

Problems solved by technology

[0005] 2) The radiant heating zone mainly heats the steel strip through the radiant heat of the radiant tube, the heating speed is slow, the heating time is long, and a long furnace section is required; and due to the influence of factors such as the structure of the heating element, the arrangement method and the safety of the equipment, the heating is uniform bad sex;

[0006] 3) The rapid cooling zone adopts wet cooling such as water quenching or water mist, which is difficult to control the shape of the strip, and the subsequent strip surface cleaning process is required, otherwise the strip surface quality will be affected

Images