This standard specifies the basic principle and requirements for the selection of shaft and bearing housing hole fits for rolling bearings (hereinafter referred to as "bearings") under general operating conditions.
Note: general operating conditions refer to the conditions of the host without special requirements for running accuracy, operation smoothness, operating temperature, etc.
The fits specified in this standard are applicable to the following conditions:
a) The boundary dimensions of the bearings comply with GB 273.1-2011, GB 273.2 -2006 and GB 273.3-2015, and their nominal inside diameter d≤500mm;
b) The tolerances of the bearings comply with Grades 0 and 6(6X) in GB 307.1-2005;
c) The clearances of bearings comply with Group N in GB 4604.1-2012;
d) The shafts are solid or made of thick-walled steel;
e) The housings are made of steels or iron castings.
This standard is not applicable to the bearings without inner (outer) ring or the bearings for special purpose (such as airframe bearings, instrument bearings, and main shaft bearings of machine tools).
