The engine crankshaft of some small wheeled tractors is supported by two rolling bearings. The rolling bearing consists of an inner ring, an outer ring, a rolling body and a cage. The outside of the inner ring and the inside of the outer ring are provided with a raceway to facilitate the rolling of the rolling body. The inner ring is matched with the shaft, and the outer ring is matched with the bearing seat or box body. Usually, the inner ring rotates with the axis and the outer ring does not. The front and rear main journals of the crankshaft are fixed with the inner ring of the rolling bearing. The outer ring of the rear rolling bearing is fixed in the body bearing seat hole with the rear bearing cover to prevent axial movement. The outer ring of the front bearing is directly installed in the seat hole of the body, without axial fixation, so that the crankshaft is heated and expanded, and there is axial expansion room forward.
Once the rolling bearing of the engine crankshaft fails, it will directly affect the technical state of the engine. Therefore, attention should be paid to the failure of the rolling bearing. Now the common faults of the rolling bearing are analyzed as follows:
There are gaps between the inner and outer ring of the bearing and the wear of the mating parts
1. The outer ring of the bearing moves.
In order to facilitate disassembly and assembly, the roller bearing outer ring and seat hole adopt a transition fit. The maximum interference of the front bearing outer ring is 0.035mm, and the maximum clearance is 0.013mm. The maximum interference of the rear bearing outer ring is 0.016mm, and the maximum clearance is 0.06mm. In the assembly of the seat hole to be measured, the interference or clearance can not exceed the above range, otherwise, the seat hole is to be repaired.
2. The inner ring of the bearing moves.
Rolling bearing inner ring and journal adopt interference fit. The maximum and minimum interference of the front bearing inner diameter is 0.055mm and 0.012mm respectively. The maximum interference of rear bearing inner diameter is 0.046mm and the minimum interference is 0.003mm. From the above matching, if the bearing has been disassembled several times, the bearing inner ring and the journal may have gaps, and the journal must be repaired before it can be applied.
When the bearing and shaft with loose, some maintenance workers with loose shaft surface with embossing or punching method to make shaft surface hair, in an attempt to obtain a close with the surface. This not only destroys the geometry of the shaft surface, so that the bearing can not get the correct centre position in the installation and skew, but also the fluff part will eventually be flattened and become a loose fit. The correct maintenance method is to grind the journal first, and then brush or spray the journal.
High quality bearings supplier
Eric Bearing Limited, Your trustworthy bearings supplier, Variety Top Brand Bearings.
Eric Bearing Co., Ltd. has established partnerships with some distributors who have authorized world-renowned manufacturers. We have more than 8 years of export experience can help you find the ideal purchasing solution. If you are looking for Original bearings Best prices or want to confirm some technical details before you order, just need to send an email: firstname.lastname@example.org. Our professional sales will contact you within 2 hours.
Other five kinds of water-reducing agents: sulfamate high-efficient water reducer, fatty acids high-efficient water reducer, HSB aliphatic superplasticizer, powder polycarboxylate, casein will be introduced.…
GH4049 is a Ni-Co-Cr-based deposition hardening deformation superalloy, the application temperature is lower than 950℃.…
Analysts at JPMorgan recommended selling or "underweight" emerging market local currency sovereign debt because of the global impact of the Ukraine-Russia crisis.JPMorgan estimated that fixed-income assets in emerging markets have lost 6-9 percent of…