This document specifies, according to ISO？12301, the checking of the peripheral length of thin-walled half bearings with or without flange, and describes the necessary checking methods and measuring equipment.

Thin-walled half bearings are flexible and, in the free condition, do not conform to a cylindrical profile. This is one reason the peripheral length of the half bearings can only be measured under a constraining load by use of specialized measuring equipment.

In addition, measuring equipment different from that illustrated in this document can be used, provided the measuring accuracy of the equipment is consistent with the specifications given in Clause？17.

This document does not include the measurement of the parting line taper.

This document applies to thin-walled half bearings, the specifications of which are given in ISO？3548？1.