Vibration Problems And Treatment Methods Of Turbine Generator Bearings
04/07/2023Centerless Grinding Technology Of Bearing Ring Outer Circle
13/07/2023
- Use reasonable cooling methods:
The influence of the cooling process on the deformation of metal after quenching is also a very important cause of deformation. Hot oil quenching deformation is smaller than cold oil quenching, generally controlled at 100±20℃. The cooling capacity of the oil is also critical to deformation. The mixing method and speed of quenching affect the deformation. The faster the cooling speed of metal heat treatment, the more uneven the cooling, the greater the stress generated, and the larger the variable inlet bearing shape of the mold. Precooling can be used as far as possible under the premise of ensuring the hardness requirements of the mold; The use of fractional cooling quenching can significantly reduce the thermal stress and microstructure stress generated during metal quenching, which is an effective way to reduce the deformation of some complicated workpieces. For some particularly complex or high precision workpieces, the use of isothermal quenching can significantly reduce deformation.
- Use suitable media:
Under the premise of ensuring the same hardness requirements, try to use oily media, experiments and practice have proved that, under the premise of no difference in other conditions, the cooling speed of oily media is slower, and the cooling speed of water-based media is relatively fast. Moreover, compared with the oily medium, the change of water temperature has a greater impact on the cooling characteristics of the water-based medium, and under the same heat treatment conditions, the deformation of the oily medium is relatively small compared with the water-based medium nsk bearing after quenching.
- The structure of the parts should be reasonable:
In the cooling process of metal after heat treatment, the thin part is always cold fast, and the thick part is cold slowly. In the case of meeting the actual production needs, the difference in workpiece thickness should be reduced as far as possible, and the section of parts should be uniform to reduce the distortion and cracking tendency of the transition area due to stress concentration; The workpiece should try to maintain the symmetry of the structure and material composition and organization to reduce the distortion caused by uneven cooling; The workpiece should try to avoid sharp edges, grooves, etc., and there should be rounded corner transition at the junction of thickness and step of the workpiece; Minimize the structural asymmetry of holes and grooves on the workpiece; The method of reserving processing amount for parts with uneven thickness is adopted.
