Reasons affecting grinding deterioration layer of SKF imported bearing
Reasons affecting grinding deterioration layer of SKF imported bearing
2022年4月19日
Analysis of raceway noise of fag imported bearing
Analysis of raceway noise of fag imported bearing
2022年4月19日

Influence of vibration and temperature on NSK bearing in use

  • If there is crack, indentation or corrosion on the rolling surface of rolling bearing, periodic vibration and noise like riveting rivets will occur. Its cycle may be fixed, but most of it has a certain corresponding relationship with the rotating speed. The scars will occur continuously on the channel, and the scars will appear on the steel ball from time to time, and this noise will change with the installation and lubrication conditions.

Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use

  • The control methods of this kind of noise include: do not knock the bearing during installation, and prevent the INA Bearing from being installed obliquely when the ina bearing is assembled with the shaft and then installed into the bearing seat; Prevent ina bearing from rusting during storage and shock vibration during transportation; Use grease with high viscosity.
  • Dust sound and its control method
  • If there are dust and other foreign matters in the rolling bearing, aperiodic vibration and so-called dust sound will occur. The magnitude of vibration and noise is uncertain, and there may or may not be.
  • The control methods of dust noise include: improving the cleaning method of INA Bearing, and strictly cleaning the bearing, shaft, seat hole and matching parts before installation; Remove foreign matters in the lubricant; Improve the sealing of bearings; Avoid using plastic cages with impure materials or embedded foreign matters.
  • Noise caused by lubrication factors and Its Countermeasures
  • Incorrect lubricant selection, insufficient lubricant or aging hardening can lead to vibration and noise of INA Bearing, and this noise has no certain law. In this case, only select the appropriate lubricant, adjust the amount of lubricant, prolong the service life of lubricant and reasonably determine the replacement cycle.
  • The raceway sound of INA Bearing and its control method raceway sound is a smooth and continuous sound made by the rolling body rolling on the raceway surface when the shaft is running. It is a unique basic sound that will occur in all rolling bearings. The general INA Bearing sound is the sound of raceway plus other sounds. The raceway sound of ball bearing is irregular, and its frequency is above 1000Hz. Its main frequency does not change with the speed, but its total sound pressure level increases with the speed. 
  • For INA Bearing with loud raceway sound, the sound pressure level of raceway sound decreases with the increase of viscosity; For ina bearings with low raceway sound, the sound pressure level changes from decrease to increase when the viscosity increases to more than 20mm2 / s. The greater the rigidity of the bearing pedestal, the lower the total sound pressure level of the raceway sound. Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • If the radial clearance is too small, the total sound pressure level and dominant frequency of raceway sound will increase sharply with the decrease of radial clearance. The methods to control the sound of raceway are: select low-noise bearing, that is, INA Bearing with small waviness, and carefully select the service conditions. Raceway noise often affects the noise of the whole machinery. Reducing raceway noise can reduce the noise of the whole machinery.
  • Impact sound of rolling element and its control method when the ball bearing or cylindrical roller bearing of larger model runs at low speed under pure radial load, due to the small centrifugal force of the rolling element, the rolling element in the non load area will impact the cage or raceway and make noise. But as the speed increases, the sound will disappear. The control methods of impact sound of rolling elements include: appropriately reducing radial clearance and using INA Bearing with cage with reasonable structure and flexible material.
  • The rolling sound of INA Bearing and its control method rolling sound is the harsh metal friction sound that can occur in cylindrical roller bearings on all occasions. Most of it occurs in grease lubricated larger ina bearings, which is more likely to occur in greases with degraded base oil performance, and almost does not occur in oil lubrication.
  •  In addition, it is easy to occur in winter. When bearing pure radial load, it is easy to occur in the case of large radial clearance, and it is easy to occur in a specific speed range with different models and sizes, both continuously and intermittently. Special processing methods for the outer ring raceway can prevent the occurrence of rolling sound. If necessary, this ina bearing can be selected, or the radial clearance of the bearing can be appropriately reduced, the lubricating grease with excellent performance can be used and the rigidity of the parts matched with the bearing can be improved. Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • When disassembling the lower SKF Bearing for maintenance, first record the appearance of SKF Bearing, confirm the residual amount of lubricant, and wash the bearing after sampling the lubricant for inspection. As a cleaning agent, gasoline and kerosene are commonly used.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • The cleaning of the dismantled imported bearings is divided into rough cleaning and fine cleaning. The metal mesh pad bottom is placed in the container respectively, so that the SKF bearings do not directly contact the dirt of the container. During rough cleaning, if SKF Bearing rotates with dirt, it will damage the rolling surface of the bearing, which should be paid attention to. In the coarse cleaning oil, use a brush to remove the grease and adhesion. After it is roughly clean, turn to fine cleaning.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Fine cleaning is to carefully clean the SKF Bearing while rotating in the cleaning oil. In addition, the cleaning oil should always be kept clean.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • In order to judge whether the disassembled SKF Bearing can be reused, it is necessary to check after the bearing is cleaned, and carefully check the state of raceway surface, rolling surface and mating surface, the wear of cage, the increase of SKF Bearing Clearance, and whether there are damages and abnormalities related to the decline of dimensional accuracy. For non separable small ball bearing, support the inner ring horizontally with one hand and rotate the outer ring to confirm whether it is smooth.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Tapered roller bearing and split SKF Bearing can inspect the raceway surface of rolling element and outer ring respectively. Since large imported bearings cannot be rotated by hand, pay attention to the appearance of rolling elements, raceways, cages and edge retaining surfaces. The higher the importance of SKF bearings, the more careful the inspection is.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Once the final value of the required rated load is determined, you must consider the overall dimensions required for the installation of SKF bearings, including the installation and fixing of SKF bearings considered here. And the size of the shaft matching the bearing with the required load rating. These factors help to determine the bearing structure and size, and some imported bearing types can be excluded. In some cases, due to space constraints, the choice is excluded even before the rated load is determined.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • For example, if the shape of SKF Bearing is very narrow, ball bearing is the type that can work here. Alternatively, if you have to use a bearing housing with a very small diameter, you need to install two or more roller bearings on the same shaft to achieve sufficient load rating.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Another common contradiction arises when the size of the shaft is very different from the required SKF Bearing Load Rating. If the shaft is large but the load is light, even if the required rated load is very small, an expensive and large SKF Bearing with high rated load must be proposed. In this case, contact the bearing manufacturer in order to put forward a cost-effective solution.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • example
  • Basic working conditions. Assuming SKF Bearing is applied to reducer, the inlet bearing must support one end of a shaft with a diameter of about 25mm, and a spur gear is installed on the shaft.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Duty cycle and SKF inlet bearing load. The analysis of the gear force and the working cycle of the transmission show that the radial load borne by the bearing is 1780n and the speed is 11000r / min in about 3 / 4 of the time, and the radial load borne by the SKF Bearing is 890n and the speed is 3500r / min in 1 / 4 of the running time. Good positive engagement produces almost no axial force, and there is no oblique engagement or other effective axial component force. It is estimated that the large axial force in both directions is 89n and the large vibration force is 89n.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Dimensional limits. Due to the limitation of the internal design of the reducer, the large outer diameter of SKF Bearing is allowed to be 70mm, the large calculated disturbance is 6, and the different axial degrees of large positions are 0 and 0015. Do not require self-aligning bearings.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • environment The lubrication of SKF bearings is the same as meshing lubrication: oil is injected from a large oil groove, and the high expected temperature is 140 F.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Reliability. SKF Bearing must have a good reliability in order to work continuously, with a reliable failure rate of 8%. Vibration is very sensitive to the damage of NSK bearing. Peeling, indentation, corrosion, crack and wear will be reflected in the vibration measurement of NSK bearing.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  •  Therefore, the vibration can be measured by using a special NSK bearing vibration meter (frequency analyzer, etc.), and the specific situation of abnormality can not be inferred by frequency division. The measured values are different due to the service conditions of NSK bearing or the installation position of sensor, so it is necessary to analyze and compare the measured values of each machine in advance to determine the judgment standard.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Then let’s take a look at the impact of temperature on the bearing. Using high temperature often indicates that NSK bearing has been in abnormal condition. High temperatures are also harmful to NSK bearing lubricants. Sometimes bearing overheating can be attributed to NSK bearing lubricant. If the temperature of bearing exceeds 125 ℃, the service life of NSK bearing will be reduced. The causes of high temperature bearings include insufficient or excessive lubrication and lubricant. It contains impurities, excessive load, NSK bearing ring damage, insufficient clearance, high friction caused by oil seal, etc.
  • Therefore, it is necessary to continuously monitor NSK bearing temperature, whether it is measuring the bearing itself or other important parts. If the operating conditions remain unchanged, any temperature change can indicate that a fault has occurred.
  • The regular measurement of NSK bearing temperature can be aided by thermometer, such as NSK digital thermometer, which can accurately measure NSK bearing temperature and display it in ℃ or Fahrenheit. Important bearing means that when it is damaged, it will cause equipment shutdown. Therefore, this kind of NSK bearing should be equipped with temperature detector. Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Generally, if the bearing is used correctly, it can be used until the fatigue life is reached. However, there will be accidental and premature damage, which is not resistant to use. This early damage, as opposed to fatigue life, limits the use of quality known as failure or accident. Most of them are caused by careless installation, use and lubrication, foreign matters invading from the outside, insufficient research on the thermal effects of shafts and shells, etc.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • As for the damage state of Timken bearing, for example, the clamping damage of the ring retaining edge of roller bearing can be considered as the reason. These reasons also coincide with insufficient lubricant, unsuitable, defects of oil supply and drainage structure, intrusion of foreign matters, bearing installation error and excessive deflection of shaft.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Therefore, only investigating the damage of Timken bearing, it is difficult to know the real cause of the damage. However, if we know the use machinery, service conditions, the structure around the bearing, understand the situation before and after the accident, and investigate the damage state of the bearing and several causes, we can prevent the recurrence of similar accidents.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Precautions for the use of Timken bearings are as follows:Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Keep Timken bearings and their turnover clean
  • Even small dust that cannot be seen by the eyes will have a bad impact on Timken bearings. Therefore, keep the surroundings clean so that dust will not invade Timken bearings.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Use with care
  • When Timken bearing is strongly impacted in use, it will produce scars and indentation, which will become the cause of the accident. In serious cases, it will crack and fracture, so we must pay attention to it.
  • Use appropriate Timken operating tools
  • Avoid replacing with existing tools and bearing tools, and appropriate tools must be used. We often emphasize the importance of tools because too many customers use the wrong tools in installation, resulting in the damage of Timken bearings.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Pay attention to the corrosion of Timken bearing
  • When operating Timken bearings, sweat on your hands can be the cause of rust. Pay attention to operate with clean hands and wear gloves as much as possible. Vibration is very sensitive to the damage of SKF Bearing. Peeling, indentation, corrosion, crack and wear will be reflected in the bearing vibration measurement. Therefore, the magnitude of vibration can be measured by using a special bearing vibration meter (frequency analyzer, etc.), and the specific situation of abnormality can not be inferred through frequency division. The measured values are different due to the service conditions of the bearing or the installation position of the sensor. Therefore, it is necessary to analyze and compare the measured values of each machine in advance to determine the judgment standard.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Next, let’s take a look at the impact of temperature on the bearing. Using high temperature often indicates that SKF Bearing has been in an abnormal situation. High temperature is also harmful to the lubricant of the bearing. Sometimes bearing overheating can be attributed to the lubricant of the bearing. If the temperature exceeds 125 ℃ for a long time, the service life of the bearing can be reduced. The causes of high temperature bearings include insufficient or excessive lubrication and lubricant. It contains impurities, excessive load, bearing ring damage, insufficient clearance, high friction caused by oil seal, etc.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Therefore, it is necessary to continuously monitor the temperature of SKF Bearing, whether it is measuring the bearing itself or other important parts. If the operating conditions remain unchanged, any temperature change can indicate that a fault has occurred.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • The periodic measurement of SKF Bearing temperature can be aided by thermometer, such as digital thermometer, which can accurately measure the bearing temperature and display it in ℃ or Fahrenheit. Important bearing means that when it is damaged, it will cause equipment shutdown. Therefore, this kind of bearing should be equipped with temperature detector.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
Influence of vibration and temperature on NSK bearing in use
  • Maintaining IKO imported bearings is a necessary condition for bearing operation. The common maintenance is for bearing lubrication. After reading how to select the bearing lubrication mode and understanding the bearing lubrication mode, it is also necessary to understand the bearing system maintenance. Let’s see how to carry out IKO imported bearing lubrication and maintenance.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Keep the bearings lubricated clean
  • Before inspecting the bearing imported from IKO, Sweden, the surface of the bearing should be cleaned first, and then the oil seal of the bearing and its surrounding parts should be carefully inspected. If there are bad symptoms, it must be replaced. The bad oil seal will cause damage, make the cloud of the bearing abnormal and cause the shutdown of the equipment.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Take care to cover exposed bearings
  • When inspecting the bearing, do not expose the bearing to pollutants or moisture. If the work is interrupted, the machine shall be covered with oil paper, plastic sheet or similar materials. If it is possible to clean the naked bearing without disassembly, clean it with a brush coated with petroleum solvent, and then wipe it dry with a piece of lint free cloth or blow it dry with compressed air (be careful not to start the rotation of the bearing assembly). Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Use a small mirror and a probe similar to that used by dentists to check the track surface, retainer and beads of the bearing. Do not clean the sealed cover or dust-proof bearing; Just wipe the outer surface. If the bearing is damaged, it needs to be replaced. It is much more economical to replace the bearing during the regular shutdown and maintenance period than the loss of sudden shutdown due to the damage of the array bearing.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Check the lubricant of the bearing
  • Lubricants are important not only for bearings, but also for all IKO imported bearings. However, please note that Japanese bearings should not add too much grease. Then it’s time to change the lubricant of the bearing. After draining the old engine oil, if possible, the bearings lubricated with engine oil should be filled with fresh engine oil and let the machine rotate at low speed for a few minutes.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  •  Make the oil collect residual pollutants as much as possible, and then drain the oil. When replacing the grease of the bearing lubricated with grease, the Joe remover used shall avoid the contact of cotton with any part of the bearing. Because these residual fibers may wedge between rolling parts and cause damage, especially in bearing applications.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • Through these three steps, you can well maintain your bearing, greatly increase its service life and save your operation cost.
  • Not only the surface quality of IKO imported bearing workpiece is poor, but also the crystal corrosion resistance of the workpiece is reduced. When the imported IKO bearing workpiece is seriously overheated, it will produce coarse grains and increase the volume of 8 iron cable in the steel, which is easy to deteriorate the hot working performance of the workpiece. When lCrl8Ni9Ti stainless steel companion or flange parts are overheated, orange peel surface defects are easy to occur.
  • To this end, the following preventive measures are proposed:
  • Strictly control lcrl8ni9]ri the forging heating temperature and heating and holding time of stainless steel box and flange parts to prevent the workpiece from overheating and coarse grain defects.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • In the production of workpiece forging, if the forging ratio is too small and the final forging temperature is too high, it is also easy to have coarse-grained structure defects. The forging ratio of workpiece should be appropriate and sufficient and the final forging temperature should be moderate.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • The solution treatment temperature of IKO imported bearing workpiece should not be too high, the holding time should not be too long, the heating temperature should not be higher than 1150 “C, and the holding time should be calculated as 1-l_5min / mm.Influence of vibration and temperature on NSK bearing in useInfluence of vibration and temperature on NSK bearing in use
  • For the coarse workpiece with overheated structure, the method of forging and refining grain can be used to eliminate the defects, prevent the orange peel surface defects of the workpiece during cold deformation, and improve the surface quality of the workpiece.