What are the requirements for needle roller bearings to assemble mechanical equipment?

1. Before assembling the needle roller bearing, measure the matching size of the bearing, and choose an appropriate method to clean it according to the anti-rust method of the bearing; the bearing should be free of damage, corrosion, and rotation should be sensitive and no abnormal noise.

　　2. When using the temperature difference method to assemble needle roller bearings, the heating temperature of the bearing should not be higher than 100℃; the cooling temperature should not be lower than /80℃.

　　 3. The matching of the outer ring of the bearing with the bearing seat or box hole should conform to the rules of the equipment technical file. Regarding split bearing seats or open boxes, the split joint surface should be free of gaps; the outer ring of the bearing and the bearing seat should be evenly in contact with the bearing cap within the range of 120° of the symmetric centerline and the bearing cap within the range of 90° of the symmetric centerline, and A 0.03mm feeler gauge should be used for inspection, and the insertion length should be less than 1/3 of the outer ring length. There shall be no clamping phenomenon between the outer ring of the bearing and the semicircular holes of the bearing seat or open box body.

　　4. The bearing should be close to the shaft shoulder or the bearing seat shoulder; the clearance between the tapered roller bearing and the radial thrust ball bearing and the shaft shoulder shall not be greater than 0.05mm, and the clearance with other bearings shall not be greater than 0.1mm. The bearing caps and washers must be flat, and should be evenly attached to the end face of the bearing. When there are rules in the equipment technical file, a gap can be left in accordance with the rules.

　　 5. When assembling a radial bearing with non-adjustable radial clearance at both ends of the shaft, and the axial displacement of the shaft is a radial bearing limited by the end caps, a clearance should be left. When the equipment technical documents are irregular, the clearance can be 0.2～0.4mm.

　　 6. Radial bearings, needle roller bearings, and spiral roller bearings should rotate sensitively after assembly. When using lubricious grease bearings, 65% to 80% of the cavity volume should be filled with clean lubricating grease after assembly, but lubricating grease should not be added to thin oil lubricated bearings.

7. The axial preload level (axial pre-interference) of single-row radial ball bearings, radial thrust tapered roller bearings, and radial thrust ball bearings mounted on the journal and in the bearing seat shall be in accordance with the bearing specification or The implementation of the rules of the equipment technical documents.