Fits for radial roller bearings

The main dimensions of radial roller bearings have tight tolerances. In order to achieve a good bearing seat while at the same time being easy to assemble, the outside diameter of the shafts or the inside diameter of the bores are tolerated according to the fit system. The recommended shaft and bore fits are given below.

Recommended fit for the shaft

Load Shaft diameter Dimensional tolerance
Light loads
(P ≤ 0,05 C)		 Dw ≤ 25 mm j6
25 < Dw ≤ 60 mm k6
60 < Dw ≤ 140 mm m6
Normal to high loads
(0,05 C < P ≤ 0,1 C)		 Dw ≤ 30 mm k6
30 < Dw ≤ 50 mm m6
50 < Dw ≤ 65 mm n5
65 < Dw ≤ 100 mm n6
100 < Dw ≤ 280 mm p6
280 < Dw ≤ 500 mm r6
Dw > 500 mm r7
High to very high loads
(P > 0,1 C)		 50 < Dw ≤ 65 mm n5
65 < Dw ≤ 85 mm n6
85 < Dw ≤ 140 mm p6
140 < Dw ≤ 300 mm r6
300 < Dw ≤ 500 mm r6 + IT6
Dw > 500 mm r7 + IT7
C = basic dynamic load rating | P = equivalent dynamic bearing load | IT = basic tolerance
Dimensional tolerance limits

Recommended fit for the bore

Load Limitation Dimensional tolerance
Point load on the outer ring. e.g.:
Puknktlast am Außenring Punktlast am Außenring
Heat supply through the shaft none G7
Light to normal loads (P ≤ 0,1 C) none H8
High loads (P > 0,1 C) none H7
Indefinite load direction Light to normal loads (P ≤ 0,05 C) keine J7
Normal to high loads (P > 0,05 C) Only for unsplit housings K7
High impact loads Only for unsplit housings M7
Circumferential load on the outer ring, e.g.:
Umfangslast am Außenring Umfangslast am Außenring Umfangslast am Außenring
Small and variable loads (P ≤ 0,05 C) Only for unsplit housings M7
Normal to high loads (0,05 C < P ≤ 0,1 C) Only for unsplit housings N7
Very high loads (P > 0,1 C) Only for unsplit housings P7
C = basic dynamic load rating | P = equivalent dynamic bearing load
Dimensional tolerance limits

This information is to be seen as a recommendation. The data has been carefully compiled from various sources, but no guarantee is given for any information.