Select NTN bearing model with high load capacity
Select NTN bearing model with high load capacity
2022年5月11日
Three principles of how to prolong the service life of NTN bearings
Three principles of how to prolong the service life of NTN bearings
2022年5月12日

Inspection of vibration fault of punching outer ring needle roller bearing during operation

Measurement of shaft vibration needle roller bearing during operation

  • The bearing shall be cleaned with gasoline or kerosene before installation, and used after drying, and good lubrication shall be ensured. Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Double row deep groove ball bearings are generally lubricated with grease or oil. When grease lubrication is used, the grease with excellent functions such as no impurities, oxidation resistance, rust prevention and extreme pressure shall be selected.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  •  The filling amount of lubricating grease is 30% – 60% of the volume of bearing and bearing box, which should not be too much. The double row deep groove ball bearing with sealing structure has been filled with grease. Users can use it directly and can’t clean it again.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • When installing the bearing, the bearing must apply equal pressure on the circumference of the ferrule end face to press the ferrule in. It is not allowed to directly knock the bearing end face with hammers and other tools to avoid damaging the bearing. Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • When the interference is small, press the end face of the bearing ring with the sleeve at room temperature, knock the sleeve with a hammer, and press the ring evenly through the sleeve. Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • If installed in large quantities, hydraulic press can be used. When pressing in, ensure that the end face of the outer ring and the end face of the shell shoulder, and the end face of the inner ring and the end face of the shaft shoulder are pressed tightly without clearance.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Measure the size of the shaft and bearing seat hole to determine the matching accuracy of the bearing. The matching requirements are as follows: the inner ring and the shaft adopt interference fit, and the interference amount is 0 ~ + 4 μ M (0 under light load and high precision); Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Clearance fit is adopted between the outer ring and the bearing seat hole, and the clearance is 0 ~ + 6 μ M (but when the angular contact ball bearing is used for the bearing at the free end, the clearance can also be increased); Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The roundness error between shaft and seat hole surface is 2 μ M below, the end face parallelism of spacer used for double row deep groove ball bearing is 2 μ M below, the runout of the inner end face and outer end face of the shaft shoulder is 2 μ Below m; The runout of the shoulder of the bearing seat hole to the axis is within 4 μ Below m; The runout of the inner end of the front cover of the main shaft facing the axis is within 4 μ Below M.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Installation of fixed end front bearing on the shaft: thoroughly clean the double row deep groove ball bearing with clean cleaning kerosene. Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • For grease lubrication, first inject the organic solvent containing 3% ~ 5% grease into the bearing for degreasing and cleaning, and then fill the quantitative grease into the bearing with an oil gun (accounting for 10% ~ 15% of the bearing space volume); Heat the bearing to raise the temperature by 20 ~ 30 ℃, and install the bearing into the shaft end with an oil press; Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Press the set sleeve on the shaft and press the bearing end face with appropriate pressure to make it axially positioned; Roll the belt of the spring scale on the outer ring of the bearing and check whether the specified preload changes greatly by measuring the starting torque (even if the double row deep groove ball bearing is correct, the preload may also change due to the deformation of the fit or cage).Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Let’s briefly introduce the rolling sound of the bearing first. The size and sound quality of the rolling sound should be checked by using a sound detector to check the of the stamping outer ring needle roller bearing in operation. The problem will be accurately judged with advanced tools. Even if the bearing has 
  • slight peeling and other damage, it will also produce abnormal sound and irregular sound, which can be distinguished by the sound detector.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Then, check the vibration of the outer ring needle roller bearing to see if the damage of the bearing is very sensitive. Whether peeling, indentation, corrosion, crack, wear, etc. will be reflected in the bearing vibration measurement. Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Therefore, the vibration can be measured by using a special bearing vibration meter (frequency analyzer, etc.), and the specific abnormal situation can not be inferred by frequency division. However, the values measured by each machine are different due to the service conditions of the bearing or the installation position of the sensor, so it is necessary to analyze and compare the measured values of each machine in advance to determine the judgment standard.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Contact measurement can be used to measure the axial vibration of punched outer ring needle roller bearing. A black gold contact surface is adopted, which is directly pressed on the journal surface with a spring. The black gold is rigidly connected with an extended metal rod and passes through the bearing bush, and the black gold surface is close to the rotor surface. 
  • Therefore, the vibration of the black gold surface directly reflects the axial vibration, and the vibration of the extension rod rigidly connected with the black gold surface also reflects the axial vibration. Using eddy current sensor to measure the vibration of metal extension rod avoids the interference to the bearing vibration measurement when the coil outlet passes through the excitation current.
  • For the treatment of the axial vibration of the rear bearing, in order to ensure the lift of the shafting on site, the elevation of the stamped outer ring needle roller bearing or the bearing of the exciter is often raised, resulting in serious side contact of the rear bearing, resulting in large vibration of the rear bearing. 
  • The rear bearing is preset to be inclined, so that the contact between the bearing bush and the journal is better, which not only ensures the contact of the bearing bush, but also conforms to the lift of the shaft system, and has received good results. 
  • At the same time, the spherical surface of the shaft must be grinded well to give full play to the self positioning function of the bearing bush. In addition, the tightening force of the bearing bush shall be adjusted properly and the foot screw shall not be loose. In this way, the problem of large axial vibration of the rear bearing can be properly handled.
  • When there is neither the error of axial vibration measurement nor the problem of large axial vibration caused by the contact of rear bearing pad edge, it is analyzed and judged that the axial vibration exceeding the standard is true, and the vibration is power frequency, the vibration can be improved through on-site high-speed dynamic balance. As long as the method is appropriate, basically one balance can be successful, up to two times.
Inspection of vibration fault of punching outer ring needle roller bearing during operation

Treatment of large roller bearing during operation

  • Proper material selection is still a factor that must be considered in bearing failure analysis. The main task of failure analysis of double row angular contact ball bearing is to find out the main factors causing bearing failure according to a large number of background materials, analysis data and failure forms.

so as to put forward targeted improvement measures, needle roller bearing during operation

  • prolong the service life of the bearing and avoid sudden early failure of the bearing. The installation condition is one of the primary factors in the use factors. Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The improper installation of the bearing often leads to the change of the stress state between the parts of the whole set of bearing, and the double row angular contact ball bearing operates in an abnormal state and fails early. According to the technical requirements of bearing installation, use, maintenance and repair, monitor and inspect the load, speed, working temperature, vibration, noise and lubrication conditions borne by the running bearing.
  •  If any abnormality is found, immediately find out the cause and adjust it to make it return to normal. Double row self-aligning roller bearing is a precision component, and its use must be carried out with corresponding caution. No matter how high-performance bearings are used, if they are not used properly, the expected high performance will not be obtained. Precautions for the use of bearings are as follows.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • As soon as the double row self-aligning roller bearing moves, the inner ring takes the raceway surface of the outer ring. Because the rolling element is in rolling contact, the running track is a dark surface, and the running track attached to the raceway surface is not very important. Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • Therefore, the load premise can be known. Therefore, under the environment of removing the bearing, what types of bearing seals are there. Please pay close attention to and observe the running track of the raceway surface. If you carefully observe the running track, you will be able to bear radial load, large axial load, torque load, or there is no extreme rigidity inequality on the bearing housing.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • When removing the double row self-aligning roller bearing for inspection, first make appearance records by photography and other methods. In addition, confirm the amount of remaining lubricant and sample the lubricant before cleaning the bearing.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The cleaning of double row self-aligning roller bearings is divided into rough cleaning and fine cleaning, and a metal grid can be placed at the bottom of the container.Inspection of vibration fault of punching outer ring needle roller bearing during operation

During rough cleaning, needle roller bearing during operation

  • use a brush to remove grease or adhesion in the oil. At this time, if the bearing is rotated in oil, pay attention to the damage to the rolling surface due to foreign matters.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • During fine cleaning, the double row self-aligning roller bearing shall be slowly rotated in oil and shall be carried out carefully.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The commonly used cleaning agent is neutral water-free diesel oil or kerosene, and sometimes warm lye is used as needed. Always use whatever cleaning agent you use. After cleaning, apply antirust oil or antirust grease on the double row self-aligning roller bearing immediately.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  •  The limit speed of rolling bearing is the allowable high speed under certain load and lubrication conditions, which is related to many factors, such as bearing type, size, load size and direction, lubricant type and lubrication mode, clearance, cage structure and cooling conditions.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The factors affecting the limit speed are: load size, load type and direction, lubricant and lubrication mode. Experience has proved that the ultimate speed of the bearing can also be improved by improving the manufacturing accuracy of the bearing, appropriately increasing the clearance of the bearing and adopting the cage of special material and structure.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The reasons for high bearing temperature include: the quality of lubricating oil does not meet the requirements or deteriorates, and the viscosity of lubricating oil is too high; The mechanism assembly is too tight (insufficient clearance); The assembly of one-way bearing is too tight; The bearing race rotates on the shaft or in the shell; Excessive load; Broken bearing cage or rolling element, etc.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The rolling bearing is allowed to make slight running noise during operation. If the noise is too loud or there is abnormal noise or impact sound, it indicates that the bearing is faulty.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The causes of rolling bearing noise are complex. One is the wear of the mating surfaces of the inner and outer rings of the bearing. The bearing deviates from the axis at high speed, which leads to the wear of the bearing and the bearing at the correct position. Inspection of vibration fault of punching outer ring needle roller bearing during operationInspection of vibration fault of punching outer ring needle roller bearing during operation
  • When Timken bearing is tired, its surface metal will peel off, which will also increase the radial clearance of the bearing and produce abnormal noise. In addition, insufficient bearing lubrication, dry friction and bearing breakage will produce abnormal sound. After the bearing is worn and loosened, the cage is loose and damaged, which will also produce abnormal noise and damage to the bearing.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • During the disassembly and inspection of rolling bearing, the fault and damage cause of one-way bearing can be judged according to the damage of bearing.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • The so-called constant pressure preload is the use of coil springs and Belleville springs to give the load-bearing of appropriate preparation methods.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • When in use, even if the relative position of the bearing changes, the preloading method. What are the seal types of the bearing when in use?, It will even change its relative position, and the preload can be maintained at a certain level.Inspection of vibration fault of punching outer ring needle roller bearing during operation
  • After metal heat treatment, in the cooling process, the thin part always cools fast and the thick part cools slowly. Under the condition of meeting the actual production needs, the great difference between the thickness of the workpiece should be reduced as far as possible, and the section of the part should be uniform as much as possible, so as to reduce the distortion and cracking tendency in the transition zone due to stress concentration; 
  • The symmetry of structure, material composition and structure of the workpiece shall be maintained as far as possible to reduce the distortion caused by uneven cooling; Sharp edges, corners, grooves, etc. shall be avoided as far as possible, and fillet transition shall be provided at the thickness junction and steps of the workpiece;
  •  Try to reduce the asymmetry of hole and slot reinforcement structure on the workpiece; The method of reserving processing quantity is adopted for parts with uneven thickness.
  • Bearing maintenance: in order to maintain the original performance of the bearing in good condition for as long as possible, it must be maintained and overhauled in order to prevent accidents, ensure the reliability of operation and improve productivity and economy.