Welding repair method for broken teeth of large gear of ball mill

Abstract

The invention discloses a welding repair method for broken teeth of a large gear of a ball mill. The method comprises the steps that 1, a welding rod is dried and placed in a heat preservation barrelfor standby application; 2, a groove is prepared, specifically, the shape and size of the groove need to be considered when cracks are dug, the groove size needs to be small and no sharp corners or dead corners exist under the condition that the cracks are thoroughly removed, welding is facilitated, and the groove and the two sides of the edge of the groove are ground to have metallic luster within the range of 15-20mm; 3, manual arc welding is adopted for welding; 4, hammering is conducted in time after welding of each section is completed so as to eliminate welding stress; and 5, grinding treatment is conducted after welding is completed. According to the field conditions, in order to obtain a welding seam with the mechanical property meeting the requirement, a proper welding material isselected, and the gear is repaired through a cold welding method. After welding repair, no crack defect is found in dye penetrant inspection, the hardness value meets the requirement, and a good using effect is achieved.

Description

technical field [0001] The invention relates to a ball mill, in particular to a welding repair method for a broken tooth of a large gear of a ball mill, and belongs to the technical field of mechanical equipment repair and processing. Background technique [0002] Broken teeth of the large gear of the ball mill are relatively common equipment defects in industries such as electric power, chemical industry, and metallurgy that use steel ball mills. However, companies in the industry do not have the technical ability to repair broken teeth. Manufacturers who specialize in welding technology will deal with it. Whether it is changing gears or outsourcing repairs, the price is relatively expensive. For example, during the dismantling and overhauling process of coal mill A of coal mill D of furnace #2 in a certain factory, it was found that one tooth of the large gear was broken, with a fracture length of 450mm and a maximum fracture depth of 75mm. The steel used for the large ge...

AI Technical Summary

Problems solved by technology

In addition, this type of steel has a small thermal conductivity, a large thermal expansion coefficient, poor welding performance, a large residual stress after welding, and is prone to cracks. It is limited to site conditions and cannot be pre-welded and welded with common tools such as crawler heaters. Post-heat treatment work, so the repair technology is difficult, and it is not easy to guarantee the repair quality