Design method of creep life of large-sized bright annealing muffle tube and like

Abstract

The invention discloses a design method of creep life of a large-sized bright annealing muffle tube and the like. According to the method, experimental simulation and numerical simulation are combined, and the service life of an upper section of a designed muffle tube is close and equal to the service life of a lower section of the muffle tube. The method comprises the following steps of: calculating heat flux density of an inner wall of the muffle tube; simulating and calculating temperature on the muffle tube; performing tensile creep and lasting creep experiments to solve a theta mapping constitutive model parameter and a Larson-Miller parameter; calculating stress of H section, obtaining creep deformation life limit and creep lasting life limit when the strain is 0.3 according to calculated temperature and judging the life of the muffle tube of the H section; keeping that the life of the upper section is equal to the life of the lower section to obtain the stress of G section when the strain is 0.3, subsequently solving the creep lasting life limit of the section, judging and determining the stress of the G section and calculating the thickness of the G section; calculating the stress of F section and determining the length of the G section and the thickness of the F section; and determining the thickness and the length of each section at the upper end one by one. According to the muffle tube designed by the method, the overall service life can be prolonged.

Description

technical field [0001] The invention belongs to the field of metallurgy and relates to a design method for the creep life of large bright annealing muffle tubes and the like which are mainly used in large vertical bright annealing muffle furnaces to realize the bright annealing process of strip steel. Background technique [0002] In recent years, stainless steel bright plate (BA plate), which is widely used in industries such as automobiles, electronics, construction, home appliances and hardware, is becoming more and more popular due to its good corrosion resistance and mirror-like brightness. The bright annealing process is the key process for producing bright stainless steel plates, and the large bright annealing furnace is the main equipment of the bright annealing production line, such as figure 1 Shown is a typical muffle furnace structure. There is a bright annealing muffle tube in the muffle furnace, which is filled with protective gas, and 40 LPG gas burners arran...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to propose a design method for bright annealed muffle tubes to meet equal creep life, to solve the problem of large differences in creep deformation and lasting life in different parts of the original muffle tube, and to make the muffle tube different areas on the upper and lower sides The creep deformation of the segment is close to equal in the same time of use, which can prolong the overall service life of the muffle tube, reduce the number of repairs and replacements, and greatly save costs

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