Repair method for severe cracking of T-shaped weld joint of blast furnace shell

Abstract

The invention discloses a repairing method for severe cracking of a T-shaped weld joint of a blast furnace shell. The repairing method comprises the following steps: the cracking part of the T-shaped weld joint is cleaned; a lining plate is machined according to the shape and size of the cleared T-shaped welding seam cracking part, the lining plate is made of the same material as the furnace shell, the shape of the lining plate is the same as that of the cleared T-shaped welding seam cracking part, and the size of the lining plate is slightly larger than that of the cleared T-shaped welding seam cracking part; and a lining plate is welded to the cleared T-shaped welding seam cracking part, the lining plate is located on the inner side of the furnace shell, the lining plate is matched with the cleared T-shaped welding seam cracking part, the cleared T-shaped welding seam cracking part is welded, and a high-toughness welding rod is adopted as a welding material for welding. The repairing method is simple in overall operation and capable of effectively repairing the serious cracking position of the T-shaped weld joint of the furnace shell, and has great application prospects.

Description

Technical field [0001] The present invention relates to the maintenance technology of ironmaking blast furnace equipment, relating to the repairing method of severe cracking of blast furnace shell butt weld, in particular to a repair method that can solve the severe cracking of blast furnace shell welds and repeated welding. Background technique [0002] In the long operating state, the original weld on the furnace shell often occurs cracks in defects such as bite, surface molding, and the occurrence of cracks will greatly affect the safety of the blast furnace operation, so repair welding. The crack is inseparable. The most commonly used weld crack repair method is to replace, but the soldering operation is more complicated, often fail, and the number of solders in the same position cannot exceed twice. Conventionally, in order to alleviate the pressure at the weld cracks, the rigid reinforcing plate is often welded on the surface of the weld, not only the angular weld weld is l...

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Problems solved by technology

[0002] When the blast furnace is in operation for a long time, the original weld seam on the furnace shell will often have cracks due to defects such as undercut and poor surface shape. The appearance of cracks will greatly affect the safety of the blast furnace operation. crack urgent

The most common method of repairing weld cracks is repair welding, but the repair welding operation is more complicated and often fails, and the number of repair welding at the same position cannot exceed two

Conventionally, in order to relieve the pressure at the weld crack, a rigid reinforcing plate is often welded on the surface of the weld. This operation not only has a large amount of welding of the fillet weld, but also because the weld is rigidly fixed, the cracked weld can only be quickly moved to the weak part. Extending will often increase the development speed of weld cracks. No matter how good the welding quality is after gouging, the problem of internal thermal expansion will not be solved. Also, the welding position is very bad, and the welding quality is difficult to guarantee. The weld treatment should not exceed two times. Multiple treatments have resulted in thick widmansite in the internal structure of the weld, with almost no toughness, so that the weld will crack quickly as long as it is stressed

[0003] Therefore, it is of great practical significance to develop a repair method that can solve the severe cracking of blast furnace shell welds and cannot be repaired after repeated welding.

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