① When the bearing inner diameter tolerance zone and shaft tolerance zone constitute a fit, in the general base hole system originally belongs to the transition with the tolerance code will become over win with, such as k5, k6, m5, m6, n6, etc., but over win is not big; When the bearing inner diameter tolerance generation and h5, h6, g5, g6, etc. constitute a fit, not in the gap and become over win with.
② bearing outer diameter tolerance zone due to the tolerance value is different from the general reference shaft, is also a special tolerance zone, in most cases, the outer ring is installed in the shell hole is fixed, some bearing parts structural requirements and need to be adjusted, and its fit should not be too tight, often with H6, H7, J6, J7, Js6, Js7 and so on with.
In general, the shaft is generally marked 0 ~ +0. 005 If it is not often dismantled, it is +0. 005 ~ +0. 01 interference fit can be, if you want to often dismantle is the transition fit can be. We also have to take into account the shaft material itself in the rotation of the thermal expansion, so the larger the bearing, Z is -0.005 ~ 0 clearance fit, Z is not more than 0.01 clearance fit!
1, bearing and shaft technetium with base hole system, bearing and shell technetium with base shaft system.
Bearing size tolerance and rotational accuracy of the value of GB307-84 corrosion-resistant pump according to the provisions.
2, and bearing with the journal and bearing box bore according to GB1031-83 technetium regulations, journal roughness Ra value is less than 1.6μm, bearing box bore roughness Ra value is less than 2.5μm.
3, with GCr15 and ZGCr15 steel manufacturing bearing collar and roller, the collar and roller hardness value should be embraced 61 ~ 65HRC; with GCr15SiMn and ZGCr15SiMn steel manufacturing, the hardness value should be embraced 60 ~ 64HRC. hardness checking method and the same part of the hardness uniformity in accordance with the provisions of JB1255.
4, check the bearing radial clearance and axial clearance should be consistent with the provisions of GB4604-84 technetium.
5, rolling bearing inner and outer ring raceway should be no spalling, serious wear, inner and outer ring are no after cracks; ball should be no wear, no serious deformation of the cage, no abnormal noise and vibration when rotating, stopping should be gradually stop gap.
6, for C tolerance tapered roller bearings, its roller and ring raceway bottom contact accuracy, water pump with a certain load for shrimp, into a good colouring check, contact traces should be continuous, contact length no should be less than the roller bus de 80.
1, for radial thick wall tile
①Press the lead method, lift the shaft method or other methods to measure the bearing clearance and tile shell pot filling amount, shaft clearance in line with bring to seek, tile shell GuoYing amount should be embanked 0 ~ 0.02mm.
② check the components, there should be no damage and cracks, shaft tile should be no spalling, porosity, cracks, grooves and partial grinding burns.
③ Shaft tile and journal de contact condition with colouring method, check the angle should be no 60 ° ~ 90 ° (speed higher than 1000r/min technetium to take the isthmus limit, speed lower than 1000r/min technetium to take the high head limit). With contact range to seek contact uniformity, each square centimetre should be followed by 2 to 4 pairs of contact points, if the contact no good, it must be into a good scraping.
④ Clean the bearing box, each oil hole is smooth, no cracks, leakage phenomenon.
⑤Tile back and bearing seat should be close and even fit, with the colouring method to check, contact area no less than 50.
①The alloy layer of axial tile and tile shell should be firmly and tightly bonded, no delamination and shelling phenomenon. The surface of the alloy layer and the two halves of the tile inside the bottom surface should be smooth, flat, no promise of cracks, pores, heavy skin, slag and bruises and other defects.
② tile back and bearing housing bore surface should be close and even fit, with the colouring method of inspection, the inner diameter is less than 180mm, its contact area no less than 85, the inner diameter is fat than or equal to 180mm bottom, its contact area no less than 70.
③ shaft tile and journal with clearance and contact condition beat by machining accuracy to ensure that the contact area generally no promise to scrape research, if along the axial contact no uniform, can be slightly trimmed.
④After assembly, with inside parting surface with 0.02mm to check the ruler, should not be able to plug into the enclosure qualified.
①Tile should be no wear and tear, deformation, cracks, scratches, delamination, crushing and burn defects; and thrust disc contact marks should be uniform, the contact area should be no less than 70 and the whole circumference of the tiles are uniform; the same group of tiles thickness should be no more than 0.01mm, the tile Bartlett should be rounded according to the direction of rotation into the oil wedge, with the benefit of lubricating oil into the back; back bearing surface is flat and smooth.
② adjustment gasket should be smooth, flat, no flexing, with a thickness difference of no fat than 0.01mm to a layer of gaskets.
③After assembling with the bearing cover, the thrust bearing clearance should be measured repeatedly by pushing the shaft method, and its value should be brought to the requested range. Measured in that way with the shaft displacement probe side of the thrust bearing clearance must be consistent, and according to the provisions of the adjustment rod displacement probe bottom indicator zero position.
④ bearing shell horizontal bonding surface is tight, no misalignment. Measure the oil temperature bottom oil hole and tile cover eye alignment, no skew. The oil hole is clean and unobstructed.