The necessity of bearing maintenance lubricant selection - bearing knowledge

Before disassembly bearings, bearing maintenance should be ready for work, the car stopped and mounting axle, to ensure the safety of the maintenance work. ( 1) , remove the bearing of the decorative cover, dust cover; ( 2) , remove the tire nut and tire, be careful not to tire bolt thread bruised. If it is a disc brake, should remove the brake, then used for pliers remove the locking collar or lock pin. ( 3) , with a special tool to remove the bearing; ( 4) , scrape off the bearing and journal and the bearing chamber of the old grease, clean with cleaner bearing and shaft neck and dried with a cloth, cloth rub-up bearing inner cavity at last. ( 5) , check the bearing and the bearing race, found a crack, the fatigue spalling and bearing roller is loose wait for a phenomenon, should replace the bearing. If found a pit on the bearing race, should also be replaced. ( 6) , check the bearing inside diameter and shaft neck to cooperate, fit clearance should not be greater than zero. 1 omm, measuring axle neck, should be in vertical ground fluctuation two parts ( The place for the biggest wear parts) Measurement. If the use of fit clearance in excess of the prescribed limits, a bearing should be replaced, restore normal fit clearance. Don't allow on the shaft neck burr, pitting to narrow the gap. ( 7) , wait for after all parts meet the requirements, will release after bearing daub grease inside the bearing. ( 8) , the bearing inner cavity should be paid attention to when daub grease, grease should be packed into bearing inner until from the other side of the bearing grease. In bearing chamber and shaft epicranium apply a thin layer of grease, rust prevention effect. Note don't apply too much grease bearing cavity, otherwise will affect the heat dissipation and brake. ( 9) And will return to the journal bearing and the bearing is installed outside, adjust the shaft head nut screw on with the hand, and then with the shaft head wrench torque tighten the adjusting nut according to the rules. After tighten nut, should turn right or left bearing laps, look at the bearing installation; On the other hand, by rotating bearing and the seat right to cooperate. The bearing appropriate tightness, felt by the free rotation of the wheels is not out of the axial clearance. ( 10) , finally installed in turn lock plate, a fixed nut, tire, dust cover and decorative cover, etc. ( 11) , good bearing adjustment, after a mileage traveled ( Around 1 okm) Parking, check for dry to touch the temperature of the bearing, if fever, adjust the tight, for bearing should be readjusted, appropriate release bearing tightness. The necessity of bearing lubrication is also confirmed by experiment and practice, with 42724 bearing at 14. 3 t and a 140 km/h speed under the condition of experiment, add 5 g oil bearing can run 7 h, runs only 10 min without grease, gap between 42 times; According to traffic department, due to the bad sealing, mixed with water, sand dust bearing lubrication failure, lead to different types of bearing replacement ratio of up to 30 - 60%. This fully shows that the normal lubrication conditions, is an important prerequisite for bearing inner life to play. Reduce the friction. Grease between the roller and the inner and outer circle, in a cage with oil film formed between rolling ring in vitro, this layer of liquid lubricant can reduce and prevent the metal contact, will greatly reduce the bearing between the friction wear, but also reduces the friction between them to generate heat. Resistance to abrasion. Rolling bearing in base load will produce elastic deformation between working face; When there is a phenomenon of partial load bearing rolling will produce relative slip between working face. Fluid lubrication film can greatly alleviate the abrasion caused by the above phenomenon, so as to extend the fatigue life of bearing. Heat dissipation. Grease can generate heat flow through rolling of the rolling face and conduction ways. Shock absorption, to reduce the noise. Lubricating oil film can absorb part of the energy, still can make the concentrated load part into distributed load, have the effect of shock absorption and noise reduction. Seal. Such as grease also rise to prevent dust and moisture bearing rolling working face. Apply in some oil seal bearing grease is solely for filtration effect. Rust and corrosion resistance. Rolling bearing grease is generally good rust and rust preventer, can prevent the corrosion of the bearing.