Maintenance tips to prevent erosion of outer spherical bearings in western Henan
Posttime：2021-04-24 Hits：997The performance of the outer spherical bearing with the belt seat is different because of the different use environment, so the performance of erosion is also different, because the erosion mode is different.Bearings, of course, can not escape the fate of erosion. Here are three ways to talk about bearing erosion.
1, the cavitation
Cavitation of outer spherical bearing with base is a form of surface damage caused when solid surface contacts with liquid and moves relative to it.When the lubricating oil in the oil film of low pressure area, oil will form bubbles, the bubbles movement to high, the pressure under the action of air bubble breaking, the breaking of instant impact and high temperature, solid surface under the effect of the impact of repeated, material fatigue peeling, the friction surface appear small pits, and then developed into the cavernous scars.Cavitation often occurs in heavy load, high speed, and large variation of load and speed sliding bearings.
2. Fluid erosion
Fluid erosion of outer spherical bearings with pedestal refers to the fluid erosion caused by the intense impact of fluid on the solid surface, resulting in spot-shaped scars on the solid surface. The surface of this damage is smooth.
3. Electrical erosion
Bearing electrical erosion refers to the electric spark generated between the friction surface of the outer spherical bearing of the belt seat due to electrical leakage, which causes spotlike scars on the friction surface, which is characterized by the reciprocating damage on the surface of the hard journal.
In order to predict the fatigue life of outer spherical bearings with pedestal and judge the remaining life, it is necessary to understand all the fatigue failure phenomena of bearings, so it will take a long time.However, since rolling fatigue occurs under compressive stress at the point of contact, significant material changes will occur to achieve breakage.Therefore, in addition to the appearance of early cracks on the surface, the raceway is affected by chemical effects, and the expansion of cracks precedes the material change, the detection of material change may judge the fatigue of bearings.
Scrape the old grease in the bearing, journal and cavity, clean the bearing and journal with detergent and dry with a cloth, and finally wipe the inner cavity with a cloth.
Check the bearing and the bearing seat ring, and it is found that there are cracks, fatigue peeling and loose bearing roller, so the bearing should be replaced.If it is found that there are pitting spots on the bearing seat ring, the bearing should also be replaced.
Check the fit between the inner diameter of the outer spherical bearing of the belt seat and the journal. The fit clearance should not be greater than 0.10mm. When measuring the journal, it should be measured in the upper and lower parts of the vertical ground (which is the largest wear part).If the fit clearance exceeds the specified usage limit, the bearing should be replaced to restore the normal fit clearance.Burr or pitting on the journal is not allowed to narrow the gap.
When all the parts meet the requirements, apply grease to the inner bearing and put it in.
When applying grease to the inner cavity of the outer spherical bearing with the belt seat, it should be noted that the grease should be squeezed into the bearing until the grease comes out from the other side of the bearing.Smear a thin layer of grease in the cavity and shaft head cover to make it rust - proof.Pay attention not to smear too much grease in the chamber, otherwise it will affect heat dissipation and braking.
Install the outer bearing back to the journal, screw the adjusting nut on the shaft head by hand, and then tighten the adjusting nut with the prescribed torque with the shaft head wrench.After tightening the nuts, you should turn around a few turns to see the bearing installation;On the other hand, the bearing and the seat ring can be properly matched by rotation.At this time, the bearing tightness is appropriate, and the wheel rotates freely without feeling the axial clearance.
Finally, lock pieces, fixed nuts, tires, dust cover and decorative cover are installed in turn.
After the outer spherical bearing of the belt seat is adjusted, drive for a distance (about 10km), stop and check the temperature used for rubbing. If the temperature is hot, it is caused by the over-tight adjustment of the bearing, it should be adjusted again and the bearing tightness should be properly relaxed.
1, the cavitation
Cavitation of outer spherical bearing with base is a form of surface damage caused when solid surface contacts with liquid and moves relative to it.When the lubricating oil in the oil film of low pressure area, oil will form bubbles, the bubbles movement to high, the pressure under the action of air bubble breaking, the breaking of instant impact and high temperature, solid surface under the effect of the impact of repeated, material fatigue peeling, the friction surface appear small pits, and then developed into the cavernous scars.Cavitation often occurs in heavy load, high speed, and large variation of load and speed sliding bearings.
2. Fluid erosion
Fluid erosion of outer spherical bearings with pedestal refers to the fluid erosion caused by the intense impact of fluid on the solid surface, resulting in spot-shaped scars on the solid surface. The surface of this damage is smooth.
3. Electrical erosion
Bearing electrical erosion refers to the electric spark generated between the friction surface of the outer spherical bearing of the belt seat due to electrical leakage, which causes spotlike scars on the friction surface, which is characterized by the reciprocating damage on the surface of the hard journal.
In order to predict the fatigue life of outer spherical bearings with pedestal and judge the remaining life, it is necessary to understand all the fatigue failure phenomena of bearings, so it will take a long time.However, since rolling fatigue occurs under compressive stress at the point of contact, significant material changes will occur to achieve breakage.Therefore, in addition to the appearance of early cracks on the surface, the raceway is affected by chemical effects, and the expansion of cracks precedes the material change, the detection of material change may judge the fatigue of bearings.
Scrape the old grease in the bearing, journal and cavity, clean the bearing and journal with detergent and dry with a cloth, and finally wipe the inner cavity with a cloth.
Check the bearing and the bearing seat ring, and it is found that there are cracks, fatigue peeling and loose bearing roller, so the bearing should be replaced.If it is found that there are pitting spots on the bearing seat ring, the bearing should also be replaced.
Check the fit between the inner diameter of the outer spherical bearing of the belt seat and the journal. The fit clearance should not be greater than 0.10mm. When measuring the journal, it should be measured in the upper and lower parts of the vertical ground (which is the largest wear part).If the fit clearance exceeds the specified usage limit, the bearing should be replaced to restore the normal fit clearance.Burr or pitting on the journal is not allowed to narrow the gap.
When all the parts meet the requirements, apply grease to the inner bearing and put it in.
When applying grease to the inner cavity of the outer spherical bearing with the belt seat, it should be noted that the grease should be squeezed into the bearing until the grease comes out from the other side of the bearing.Smear a thin layer of grease in the cavity and shaft head cover to make it rust - proof.Pay attention not to smear too much grease in the chamber, otherwise it will affect heat dissipation and braking.
Install the outer bearing back to the journal, screw the adjusting nut on the shaft head by hand, and then tighten the adjusting nut with the prescribed torque with the shaft head wrench.After tightening the nuts, you should turn around a few turns to see the bearing installation;On the other hand, the bearing and the seat ring can be properly matched by rotation.At this time, the bearing tightness is appropriate, and the wheel rotates freely without feeling the axial clearance.
Finally, lock pieces, fixed nuts, tires, dust cover and decorative cover are installed in turn.
After the outer spherical bearing of the belt seat is adjusted, drive for a distance (about 10km), stop and check the temperature used for rubbing. If the temperature is hot, it is caused by the over-tight adjustment of the bearing, it should be adjusted again and the bearing tightness should be properly relaxed.
