What are the maintenance standards of shearer components?

2020-09-24

1、 Hydraulic pump, valve < / P > < p > 1, gear pump < / P > < p > 1.1 after maintenance, the fit clearance of main parts of gear pump shall meet the following requirements: < / P > < p > A. H7 / F7 coordination shall be maintained between the tooth top circle and the pump shell, and the surface roughness of the pump shell shall not be greater than 0.4. The axial clearance between gear and pump cover should be 0.03 ~ 0.05mm, and the clearance between two-way operation should not exceed 0.08mm. All kinds of valve bodies shall not be magnetic, and the mating surfaces shall be free of burr, scratch, rust and pitting. &The fitting surfaces of various valves need to be prepared. < / P > < p > 2.3 the surface roughness of the fitting surface and sealing surface of the slide valve shall not be greater than 0.1, and the surface roughness of other valve fitting surfaces shall not be greater than 0.4. The fit clearance between valve stem and valve hole is 0.01-0.03mm. The increase of clearance after wear shall not exceed 1 / 3 of the original design requirement. The reversing stability of the solenoid valve shall meet the following requirements: < / P > < p > A. under the rated pressure of the hydraulic system, the reversing and resetting must be fast, flexible and reliable, and there shall be no leakage and jamming phenomenon; < / P > < p > B. when the voltage drops to 85% of the rated voltage, the solenoid valve shall be able to operate normally. (2) after the casing and mechanical parts are repaired, the dimensional accuracy, roughness, center distance and form and position tolerance of each hole shall meet the requirements of technical documents. < / P > < p > 2. The threaded hole, positioning hole and positioning table on the casing meet the requirements of technical documents after repair. The bearing has no obvious wear trace and the clearance meets the requirements. There is no obvious plastic deformation in fasteners. All parts have no damage, obvious wear marks and deformation. 3. Traction part < / P > < p > 1. All parts should be carefully cleaned, and there should be no rust spots and dirt in the casing. The zero adjustment of servo mechanism must be accurate. Before the test, the filtered oil should be injected and the air in the pipeline system should be drained. < / P > < p > 4. All kinds of safety protection devices must be complete, sensitive and reliable, and should be set according to the specified value. Any kind of protection device should not be thrown away. 4. Cutting part < / P > < p > 1. All parts should be carefully cleaned, and the casing should be clean without dirt. After installation and adjustment, all transmission pairs meet the requirements of technical documents. The cylinder clutch handle and speed regulating handle should be flexible and reliable. < / P > < p > 4. < p > < p > 5. After the installation, there is no jamming in the manual test run. 5. The electric control box and motor shall be cleaned, connected firmly, and the wire number shall be clear. < / P > < p > 2. The cabinet and wiring device shall meet the technical requirements of explosion-proof electrical apparatus in coal mine, and shall meet the requirements of gb3836.2 & mdash; 2000. It is not allowed to throw off any protective device and circuit. All buttons and knobs are flexible, sensitive and reliable. The insulation value and adjustment value meet the requirements of technical documents. The main parts of the drum shall meet the following requirements: < / P > < p > 1.1 no crack or open welding, no damage to nozzle thread. < / P > < p > 1.2 the end face gear seat and radial gear seat of the drum shall be intact, and the hole wear shall not exceed 1 mm. The angle of repair welding tooth seat shall meet the requirements of technical documents. < p > < p > 1.3 the wear of spiral blade shall not exceed one third of the original thickness, otherwise repair welding shall be carried out. < / P > < p > 1.4 the cylindricity of the locating pin hole at the connection between the drum and the rocker arm shall not be greater than 0.8mm. The cooling spray system of

2 and shearer is in conformity with the technical documents. No deformation is required. The spray device is complete inside and outside, and the test is carried out at a rated pressure of 1.5 times. Water leakage is not allowed. There are no cracks, serious deformation or open welding on the bottom bracket and coal baffle. The flatness of the bottom bracket shall not be greater than 5mm. The wear of slipper and pin should not exceed 10 mm and 1 mm respectively. < / P > < p > 5. For shearer with chain traction, the chain guide shall not be deformed or stuck; the tension device of traction chain shall be complete and reliable. The anti-skid braking device should meet the technical requirements of documents. < / P > < p > 7. Shaping and matching of fuselage guard board. Replace all seals for hydraulic bolts < / P > < p > 8.1 and < / P > < p > 8.2 carry out pressure test and action test, and there shall be no leakage. Running in test: start under the condition of maximum displacement and no-load pressure, operate for more than 2min after reaching the nominal speed, and start to measure the displacement, which should be within the range of 95-110% of the nominal displacement. Then gradually load the graded running in. < / P > < p > 1.2 full load test: operate at rated pressure, nominal speed and maximum displacement for more than 2min, measure the displacement and calculate the volumetric efficiency & ETA & theta; according to the following, the value shall not be less than 5% of the original factory regulations. After overhaul, the volumetric efficiency of the oil pump shall not be lower than the factory regulations; if there is no factory regulation, it shall be carried out in accordance with jb2146-77 'technical specification for delivery test of hydraulic pump'. &ETA; & theta; (%) = full load displacement (at nominal speed) & times; 100% no-load displacement (at nominal speed). Overload test: under the nominal speed and maximum displacement, gradually load to 125% of the maximum output pressure or rated pressure, and operate for more than 1min without abnormal phenomenon. During the above tests, observe the external leakage, noise, vibration and temperature rise, and there shall be no abnormal phenomenon. < / P > < p > 2. After maintenance, all kinds of valves should be set according to the requirements of technical documents of the shearer. Repair and test of Jack < / P > < p > 4.1 when there are the following defects on the surface of Jack and seal ring: < / P > < p > A, axial scratch depth is less than 0.2mm, length is less than 50mm; < / P > < p > b, radial scratch depth is less than 0.3mm, length is less than 1 / 3 of circumference; < / P > < p > C, slight scratch area is less than 50mm < sup > 2 < / sup >; < / P > < p > D, scratches on the same circumference There are no more than 2 strips and no more than 2 scratches. < / P > < p > e. the coating appears slight