Bearing hole and shaft, bearing and tolerance to cooperate

Bearing and shaft, bearing and tolerance matching 2021 - hole 02 - 18 do non-standard so long, bearing and shaft tolerance matching, as well as the bearing and the hole tolerance matching, has been the use of tiny clearance fit function can be realized, and well packed. But local parts still need to have a certain accuracy. Fit tolerance ( 配合公差) Refers to the hole and shaft component with the sum of tolerance. It is to allow the gap to the amount of changes can be made. Hole and shaft position tolerance zone size and tolerance zone of the tolerance. Said the size of the hole and shaft fit tolerance of hole and shaft with precision. The size and location of the hole and shaft tolerance zone said hole and shaft with precision and cooperate with nature. The choice of tolerance grade with bearing shaft or the bearing hole tolerance grade associated with bearing accuracy. Cooperate with P0 level precision bearing shaft, its tolerance level for IT6 commonly, bearing hole for IT7 commonly. Have higher request for rotating accuracy and operational stability of occasions ( Such as motor, etc. ) , should choose shaft for IT5, bearing hole for IT6. The choice of tolerance zone equivalent radial load P into the 'light', 'normal' and 'heavy' load several ways, such as its ties with dynamic load rating of bearing C for: light load P≤ 0. 0 06 c normal load. 06C ＜P≤ 0. 12 heavy load 0 c. 12 c < P1) Shaft assembly tolerance zone of centripetal bearing and angular contact bearing shaft reference table corresponding tolerance zone of tolerance zone. For most occasions, shaft rotation and radial load direction invariable, the bearing inner ring relative to the loading direction, generally should choose the transition or interference fit. Static axial and radial load direction invariable, the bearing inner ring relative to the direction of the load is stationary, can choose transition or small clearance fit ( Too big gap is not allowed) 。 2) Shell hole tolerance zone installation centripetal bearing and angular contact bearing shell hole tolerance table with reference to the corresponding tolerance zone. Pay attention to when the choice for the direction of the load swing or rotation of the outer ring, should avoid clearance fit. Equivalent radial load also affects the size of the outer ring of choice. 3) Bearing structure form selection of rolling bearing housing, unless you have special need, the integral structure more commonly, split bearing just have trouble in the assembly, or on the advantages of convenient assembly become main consideration when using, but it cannot be applied to tight fit or with more precision, such as K7 and than K7 tighter fit, and like a tolerance level for IT6 or more precision of hole, are not allowed to adopt split housings. Bearing and shaft fit tolerance standard (1) when the bearing inside diameter tolerance zone with axle tolerance zone, in the general base hole system the central plains of transition fit tolerance code will be a win to cooperate, such as k5, k6, m5, m6, n6, etc. , but a win is; When the bearing inside diameter tolerance generation and h5, and h6, g5, when combined g6, etc, is not clearance and become a win. (2) bearing outside diameter tolerance zone due to the tolerance value is different from general datum axis, is also a kind of special tolerance zone, in most cases, the outer ring is installed in the shell hole is fixed, some bearing parts structure requirements need to be adjusted again, its shoulds not be too tight, often with H6, H7, J6, J7, Js6, Js7 to cooperate. Attachment: under normal circumstances, the shaft general standard of 0 ~ + 0. 005 if it is not often open, is + 0. 005 ~ + 0. 01 of the interference fit is ok, if you want to often disassembling is transition fit is ok. Do we have to take into account the shaft rotating at time of thermal material itself, so the greater the bearing, it is best to 0. 005 ~ 0 clearance fit, the largest and not more than 0. 01 clearance fit. One is moving coil interference, static ring gap. Bearing fit are generally transition fit, but where there are special circumstances optional interference fit, but very few. Because with bearing and the shaft is match to the inner ring and the shaft bearing, using the basic hole system, original bearing should be completely to zero, in actual use, we can also think so, but in order to prevent the bearing inner ring cooperate with the minimum limit of size of the shaft when inner ring rolling, the surface of the shaft damage, so we have zero to a few of bearing inner ring & mu; Under partial tolerance to ensure that the inner ring does not rotate, so bearing generally choose transition fit, even if is to choose the transition fit also cannot exceed 3 wire amount of interference. Cooperate with precision grade generally choose 6 level, sometimes also want to see the material, and the processing technology, theory level 7 is a partial bottom, level 5 co-operating with grinding. I usually choose is: bearing inner ring with shaft axis Kong Xuan k6 bearing outer ring and the hole coordination k6 or K7. （ In this paper, system network reproduced)