Repair method of bores of blast furnace tuyere small sleeve

Abstract

The invention discloses a repair method of bores of a blast furnace tuyere small sleeve, comprising the following steps: a. carrying out oil and rust removal treatment to the blast furnace tuyere small sleeve; b. placing the blast furnace tuyere small sleeve into a heating furnace, heating the blast furnace tuyere small sleeve to the temperature of 450 DEG C to 500 DEG C at the speed of 130 DEG Cto 160 DEG C every hour and keeping the temperature for 3 hours; c. carrying out build-up welding to the bores of the blast furnace tuyere small sleeve by a beryllium copper welding rod at the temperature of 450 DEG C to 480 DEG C, wherein the preheating temperature of the beryllium copper welding rod ranges from 300 DEG C to 350 DEG C; and d. placing the blast furnace tuyere small sleeve into theheating furnace again, keeping the blast furnace tuyere small sleeve at the temperature of 320 DEG C to 350 DEG C for 4 hours and then cooling. The repair method of the bores of the blast furnace tuyere small sleeve adopts the beryllium copper welding rod for welding and metallurgical bonding by welding fusion; the blast furnace tuyere small sleeve can not be separated and deform after welding, the service life of the repaired blast furnace tuyere small sleeve is closed to or longer than that of a new blast furnace tuyere small sleeve, and the consumption of spare parts of the blast furnace tuyere small sleeve is reduced.

Description

technical field [0001] The invention relates to a metal surface repair technology, in particular to a method for repairing the inner hole of a blast furnace tuyere sleeve. Background technique [0002] The small tuyere sleeve is a key component in the air supply system of the blast furnace. The combustion air enters the furnace through it, and the combustion air of a certain pressure continuously scours the surface of the inner hole when passing through the small tuyere sleeve, causing serious wear on the inner hole of the small tuyere sleeve. After testing, the wear of the inner hole of the small tuyere sleeve is the main factor for the damage of the small tuyere sleeve. The small tuyeres protrude into the furnace, and they are subjected to high heat load, wear of materials, and scour of molten iron and slag during work. The working conditions are very harsh and are often burned. In addition, the coal injection of the coal injection pipe will also cause the small tuyeres to...

AI Technical Summary

Problems solved by technology

Once the small sleeve of blast furnace tuyere is damaged, it is difficult to weld ordinary steel with pure copper plate, and the fusion will not be firm during welding

Welding rods with materials similar to those of pure copper plates are used, but under the existing welding process conditions, it is difficult for the welding rods to weld and fuse with the inner surface of the tuyere cover, and the welding layer will fall off during use. Therefore, the repair effect of the tuyere cover is poor.

After the blast furnace tuyere cover is damaged, most of the users dispose of it as a waste product, and the use cost of the tuyere cover remains high due to the high cost of materials

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