Standards Development

Scope

This document specifies the types of combined insert bearings in ISO 9628 and cast housings and pressed housings for insert bearings in ISO 3228, boundary dimensions and technical requirements of insert bearing units.

Purpose

Insert bearing unit is an assembly unit comprising an insert bearing and an insert bearing housing. With the self-aligning ability between the bearing and bearing housing, insert bearing units are generally used in these applications, such as agricultural machinery, construction equipment and textile machines.

ISO 9628, “Rolling bearings—Insert bearings and eccentric locking collars—Geometrical product specifications (GPS) and tolerance values” and ISO 3228, “Rolling bearings—Cast and pressed housings for insert bearings—Boundary dimensions and tolerances” specify the boundary dimensions and some technical requirements for insert bearing and housing respectively.

However, the lack of international standard for insert bearing units (assembly units) is inconvenient for international trade. Therefore, it is necessary to develop an uniform international standard about insert bearing units to specify the types of combined insert bearings and bearing housings, as well as boundary dimensions and necessary technical requirements of insert bearing units. According to resolution taken at Goteborg in May, 2023, TC 4/SC 6 decided to " launch a ballot on NWIP “insert bearing units” after the Form 4 and draft are completed and submitted" .

There are some existing national standards about insert bearing units which can be the basis for developing the uniform international standard, e.g., Chinese standards GB/T 7810—2017, “Rolling bearings—Insert bearing units—Boundary dimensions” and GB/T 27555—2011, “Rolling bearings— Insert bearing units—Specifications”, as well as Japanese standard JIS B 1557—2009, “Rolling bearings—Insert bearing unit”.