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How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life

  • NTN bearings are eroded in different ways due to different environments. Of course, bearings cannot escape the fate of being eroded. Here are three ways in which non-standard bearings are eroded.

How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life

  • 1. Cavitation
  • Cavitation erosion of NTN bearing is the form of surface damage caused by the contact and relative movement between solid surface and liquid. When the lubricating oil is in the low-pressure area of the oil film, bubbles will form in the oil. After the bubbles move to the high-pressure area, the bubbles collapse under the action of pressure.
  •  At the moment of collapse, great impact force and high temperature will be generated. Under the repeated action of this impact force, the material will fatigue and fall off, resulting in small pits on the friction surface, and then develop into sponge scars. Cavitation often occurs in non-standard bearings with heavy load, high speed and large changes in load and speed;How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • 2. Fluid erosion
  • The fluid erosion of NTN bearing means that the intense impact of fluid on the solid surface will cause fluid erosion, resulting in point scars on the solid surface, and the damaged surface is smooth;How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • 3. Electric erosion
  • The electric erosion of NTN bearing refers to the electric spark generated between the friction surfaces of non-standard bearings due to electric leakage of motors or electrical appliances, resulting in point scars on the friction surface. Its characteristic is that the damage occurs on the hard journal surface repeatedly.How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • In order to predict the fatigue life of NTN bearing and judge the remaining life, it is necessary to understand all the bearing fatigue failure phenomena, which will take a long time. However, because rolling fatigue occurs under the compressive stress at the contact point, great material changes will occur to achieve damage. 
  • Therefore, in addition to the early cracks on the surface, the chemical influence on the raceway and the crack propagation before the material change, the fatigue of non-standard bearings can be judged by detecting the material change.How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • To maintain NTN bearings, you must also master the following points:
  • 1. Regularly check the use status, and pay attention to whether there is abnormal noise and local sharp temperature rise at the part;
  • 2. Fill lubricating oil or grease regularly and quantitatively as required;How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • 3. According to the service condition of the vehicle, the lubricating oil shall be completely replaced at least once every six months and carefully checked;
  • 4. Inspection method under maintenance: clean the disassembled with kerosene or gasoline, carefully observe whether there is sliding or creep on the inner and outer cylindrical surfaces, whether there is peeling and pitting on the inner and outer raceway surfaces, whether the rolling element and cage are worn and deformed, etc., and judge whether they can continue to be used according to the comprehensive situation of non-standard bearing inspection.How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • When the rolling load changes slightly in the radial direction, the rolling load will be -2-3 This causes an offset in the direction of the load. The resulting vibration is inevitable, but can be preloaded to reduce axial loading of all rolling elements.
  • During operation, rolling across the damaged rotary table bearing components will produce a specific vibration frequency. Frequency analysis can identify damaged NTN bearing components. This principle has been used in condition monitoring equipment to detect bearing damage. 
How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life

How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life

  • The temperature will rise sharply, resulting in abnormal high temperature. The reasons are too much lubricant, too small bearing clearance, poor installation, excessive friction of sealing device, etc. In the case of high-speed rotation, the wrong selection of imported bearing structure and lubrication mode is also the reason.
  • How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • The relationship between shaft and bearing can be compatible with the shape deformation of adjacent parts when it is in close contact with bearing ring. If there is distortion during operation, vibration may occur. Therefore, the tolerance required for the machining of rotary table bearing and shaft is very important.
  • If you operate in a polluted environment, impurities may enter the rolling of NTN bearings. Vibration depends on the number, scale and composition of rolling impurity particles. 
  • Although the frequency does not produce a typical form, the reasons are poor lubrication, poor accuracy of shaft or bearing seat, bearing damage, foreign matter intrusion, etc., you can hear an annoying noise.How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • The inspection is generally divided into two situations:How to Prevent NTN Non-Standard Bearings From Being Eroded and Affect Their Service life
  • In one case, the small NTN bearing small machinery can rotate by hand to determine whether the bearing rotates smoothly.
  • In this case, it generally depends on whether the NTN bearing has poor operation caused by foreign matters, indentation, scars, etc., uneven rotating torque caused by poor installation, poor processing of mounting base, excessive torque caused by too small clearance, installation error, sealing friction, etc.
  • The second is that large machinery cannot rotate manually
  • In this case, large machinery cannot rotate manually, so turn off the power immediately after no-load start and carry out inertial operation. Check for vibration, sound, contact of rotating parts, etc. After confirming that there is no abnormality, enter the power operation.
Technical requirements for Timken non-standard bearing