1. Reasonable use of cooling method:
Metal cooling process after quenching effect on the deformation is also important a reason. Hot oil quenching oil quenching than cold deformation is small, general control in the 100-20 ℃. Oil cooling ability of deformation is also very important. The mixing way and speed of the quenching influence the deformation. The faster the cooling rate of metal heat treatment, the uneven cooling, the stress, the greater the die Structure Of NTN 6301LB Bearing http://www.fagbearings-hk.com/newproduct/NTN-6301LB-bearings-43372.html of shape. Under the premise of can ensure that the mold hardness requirements, as far as possible use precooling; Using hierarchical cooling quenching can significantly reduce the metal thermal stress and organization stress formed during quenching, is the effective method to reduce some of the more complex shape workpiece deformation; For some special complex or higher accuracy of workpiece, using isothermal quenching can significantly reduce the deformation.
2. Use appropriate medium:
On the premise of guarantee the same hardness requirements, as far as possible use oily medium, experiment and practice has proved, and other conditions under the premise of no difference, the slower cooling rate of oily medium, and the cooling speed of water medium is relatively faster. And compared with those of oily medium temperature change on the influences of aqueous medium cooling characteristics, under the condition of the same heat treatment, relatively oily medium aqueous medium bearing after quenching deformation is relatively small.
3. The parts structure more reasonable:
Metal in the cooling process after heat treatment, is always the thin part soon cold, the thick part of the cold slowly. In meet the need of actual production situation, we should try to reduce the workpiece thickness disparity, parts of section to uniform, to reduce the transition region due to stress concentration produce distortion and cracking tendency; Artifacts should keep the structure and material composition and microstructure of symmetry, in order to reduce the distortion caused by uneven cooling. Artifacts should try to avoid sharp edges, grooves, etc., in addition, the thickness of the workpiece on the border, the steps to place with rounded transition; As far as possible to reduce the workpiece hole and slot on the reinforcement structural asymmetry; Adopt the method of reserve was uneven thickness of parts.
Bearing maintenance: for as long as possible in good condition to maintain the performance of the bearing was required to maintenance, repair, in order to prevent accident arrangement to ensure the reliability of operation, improve the productivity and economy.
To maintain the best conditions of mechanical operation of the corresponding operation standard, on a regular basis. Content includes monitor running status, supplement or replacement of lubricants, remove the check on a regular basis. Points for maintenance operation, have bearing rotating the sound, vibration, temperature, the state of the lubricants and so on.
Bearing maintenance: bearing clean: remove bearing repair, first record the appearance of the bearing, confirm the residual stock of lubricant, sampling inspection with lubricant, bearing. Common use gasoline, kerosene as a cleaning agent.
Tear open come down to the bearing cleaning, rough washing and fine washing, respectively in the container, put a metal mesh bottom first, make the bearing is not direct contact with dirt from the container. Coarse when cleaning, if to spin bearing with dirt, can damage the bearing rolling surface, should be pay attention to. In coarse clean oil, use a brush to remove grease, adhesive, after clean, roughly into fine cleaning).
Fine cleaning, bearing side rotation in the cleaning of oil, while carefully cleaned. In addition, the clean oil is always kept clean.
Bearing inspection and judgment: in order to judge whether the bearing of the removed can use, check after wash bearing. Check the raceway surface, rolling surface, cooperate with the state, the abrasion of cage, the increase of the bearing clearance and has nothing to do with dimension precision falling damage, abnormal. Non separation of small ball bearings, with one hand will support level, the inner ring spinning confirm whether smooth outer ring.