A line in the rough rolling mill gear box maintenance

A line in the rough rolling mill gear box maintenance - 2018 08 - 01 1 Outlines a line in the coarse mill a total of 13 sets of gear box, all for the horizontal mill gear box, the 1 # 4 #, 5 #, 9 #, 10 # 13 # gear box the same internal structure, respectively, three speed stepless speed changing stepless speed changing, 2, 1. Each overhaul the main gear box is clean the bearing inspection, the failure bearing replacement, there are two types of all internal gear box bearing, spherical roller bearings and no guard cylindrical roller bearing inner ring. Internal transmission gear box expansion plan is as follows: figure a internal transmission gearbox parts in figure 2 a line in the rough rolling mill main failure forms of gear box bearing 1) In installation, lubrication and maintenance good work under the condition of bearing, due to periodic changes of stress, rolling element and raceway surface will produce fatigue pitting, which can generate strong vibration, noise and heat, reduce the rotating precision of bearing, bearing failure. 2) Due to improper assembly, lubrication, maintenance and other reasons, may result in bearing excessive wear, agglutination, internal and external ring fracture, rolling element and cage rupture failure forms, etc. 3 a line in the rough rolling mill gear box bearing to replace 1) Input shaft to take over the lateral bearing replacement input shaft axis parts and related tools as shown in figure 2. Input shaft took over the lateral bearing replacement must, in turn, demolition of tooth took over, bearing end cover, a maze gasket, dismantle the bearing again, back to the reverse order. Due to the coupling inner hole and cylinder & Iota; Belongs to the interference fit between shaft, interference quantity is in commonly 0. 18 mm0。 Between 20 mm, the demolition of gear tooth inherited with two sets of gas welding, uniform heating, the heating temperature & le; 350 ℃, 300 t hydraulic press and self-made clamping fixture, took over the top. Past maze liner dismantling of the welding heat, heat stroke method is adopted, the efficiency is not high, easy to cause the labyrinth packing deformation, affect the quality of maintenance, is now a labyrinth gas welding evenly heating pad using homemade disassembly tool, crown cooperate on axial gravity pull it out, this method is simple, reliable, time-saving, ensure maze liner without deformation. The final welding cooperate to remove the failure bearing destructive. Etc at shaft of mating surface after cooled sufficiently high with oil stone or sand paper to grind the repair, the new bearing to choose the original clearance 0. 12 mm0。 19 mm between the bearings, bearing heater is used after cleaning check zero defect heating, heating temperature & le; 118℃± 2 ℃, with inside diameter micrometer to measure the bearing inner diameter to calculate good began after back pack size bearing, it back in place. Labyrinth packing back to pack with bearing heater is heated to 120 ℃, tooth took over heating temperature & le; 350 ℃, tooth took back to pack by using special tools, using self-made simple tools back toothing took over, avoid hot, on foot, not only improve the efficiency of maintenance, can also reduce the risk. 2) Intermediate shaft of each shaft bearing replaced intermediate shaft bearing replacement is relatively convenient, non-effective bearing cutting, grinding shaft mating surface after cooling, choose the original clearance 0. 12 mm0。 19 mm between the bearings, bearing heater is used after cleaning check zero defect heating, heating temperature & le; 118℃± 2 ℃, with inside diameter micrometer to measure the bearing inner diameter to calculate good began after back pack size bearing, it back in place. 3) Flat head side output shaft bearing replaced flat head side output shaft bearing replaced and take over the lateral bearing replacement, demolition of flat head, bearing end cover, a maze in turn first gasket, flat head crown mention when demolition, hang up weight, with two sets of gas welding, uniform heating, the heating temperature & le; 350 ℃, with the press, weight will be a flat head. The rest of the labyrinth packing, demolition and bearing and the input shaft teeth take over the side, back to pack flat head heating temperature & le; 350℃。 4 the gearbox repair the matters needing attention in the process of 1) Bearing assembly before check the bearing inner ring and outer ring, rolling body, keep frame are in good condition, operation is flexible. 2) Bearing, axis with kerosene clean before assembly. 3) Ban beats on bearing directly with the hand, tongbang tapping. 4) The heating temperature of bearing & le; 120℃。 5) Such as shaft can back to install new bearing after cooling down. 6) Remove the hose connector with a clean plastic cloth bandage, back pack to ensure each tubing, oil pipe fixed tightly. 7) Daub is up and down in the joint surface when the sealant coating even, can't disconnect.