BS ISO 9628:2019 pdf download – Rolling bearings – Insert bearings and eccentric locking collars – Geometrical product specifications (GPS) and tolerance value
5.1 General
The bearings on one shaft are, as a rule, mounted in two or more separate housings, which are not always perfectly aligned. The outer ring has a spherical outside surface so that the bearing can be mounted in a housing with a matching spherical seating to accommodate permanent angular misalignment. The bore surface of the bearing inner ring and the eccentric locking collar may be plated or treated with a surface treatment to reduce corrosion during operation.
5.2 Bore diameter
For bearings with eccentric locking collar, the size of the eccentric feature on the inner ring and the locking collar is generally common for one metric and several inch inner ring bore sizes. The non- preferred inch bore sizes, which are given in parentheses in Tables 2 to 8, should be avoided whenever possible. Contrary to general rolling bearing practice, the inner ring bore diameter tolerance is on the plus side of the nominal bore diameter, in order that the bearing and collar can be slipped over standard size shafting.
5.3 Outside diameter of bearing
The outside diameter of the bearing corresponds (with respect to the metric bore diameter) to either diameter series 2 or diameter series 3 of ISO 15
5.4 Width of inner ring and locking device
The inner ring width (with respect to the metric bore diameter) does not conform to the requirements of dimension series 2 or dimension series 3 of ISO 15. It is determined by the requirements of space for sealing and locking devices and by the axial extension of the shaft support considered suitable for various applications. Where the locking device extends axially beyond the inner ring, the width over the locking device, called the overall width, and the location with respect to the middle plane of outer ring width of the side face limiting the overall width are important dimensions and are therefore specified in this document. Three series of overall widths are given: wide overall width, intermediate and narrow. Each of Figures 1 to 4 shows one example only of locking device design.
5.5 Width of outer ring
For bearings with a spherical outside surface, the width of the outer ring is not important, provided the range of width is known so that assembly slots in the housing can be properly dimensioned. This document therefore gives outer ring widths which range from a minimum that conforms to either dimension series 2 or dimension series 3 of ISO 15, to a maximum that provides sufficient space for various seals and relubrication holes.
5.6 Relubrication
Depending on the application, these bearings are supplied with or without means for relubrication, for example, one or more small radial holes drilled through the outer ring. The exact design and location of such means are not specified in this document. However, the width and location of a zone are given, in which any relubrication means, provided on one or both sides of the outer ring, should intersect such that the lubricant satisfactorily feeds into the bearing from the housing bore groove covering the zone.