Repair welding of the bearing

Bearing the repair welding of 2019 - 06 - 11 mill spindle on a single row circular cone roller bearings, material for the bearing steel, bearing outside diameter 360 mm outer height 81 mm thickness is 25 mm. Two transverse cracks found in use, a 76 mm long another long about 8-39 mm in depth 12mm。 The bearing does not replace parts, purchasing didn't spot. Is made of electrode arc welding repair, after more than three years to use found no crack. 1 welding preparation (1) to crack and around 40 mm area of oil and other wash clean with gasoline, with compressed air to blow dry. (2) with the grinder grinding cracks, grinding into a u-shaped groove, crack depth should more than about 3 mm; (3) in addition to the weld place, other parts of the application of asbestos board cover, prevent splash and arc scratch bearing plane; (4) choose 3 in diameter. 2 mm A502 austenitic stainless steel electrode, through 250 degrees bake 1 before welding. Along with the 5 hours; (5) use ZX5 - welding machine Type 400 silicon rectifier arc welding machine, dc reverse connection. 2 repair welding (1) the weldment to the welding position, welding short weld first, after the welding seam, using multilayer more inverse to welding. (2) when the welding current shi shoulds not be too large, 100 - 110 a advisable, to control the welding interlayer temperature, avoid overheating bearing, short pass, each section of the weld length is less than 40 mm, electrode don't swing, short arc welding quickly, to reduce the fusion, to pay attention to the molten pool in the welds, avoid to produce slag, porosity, defects such as no fusion, to fill arc crater arc pit. Each joint (3) should be staggered, after each welding a, immediately with a small hammer percussion welding, welding stress release, each welding after a careful check, no defects such as cracks after welding the next. Each section of the weld temperature should be controlled below 60 degrees between the layers. (4) after welding the natural cooling, the dimension accuracy of bearing and weld quality review, and according to the technical conditions for grinding processing. （ Graphic)