ISO 12132:2017 pdf download

ISO 12132:2017 pdf download.Plain bearings — Quality assurance of thin-walled half bearings — Design FMEA
1 Scope
This document gives guidelines for the preparation of a Design FMEA for thin-walled half bearings used in machinery, e.g. internal combustion engines (the Process FMEA is the responsibility of the supplier).
It lists the common potential failure mode(s), potential effect(s) and potential cause(s) of failure.
The numerical evaluation of risks in terms of occurrence, severity and detection can be specific to each application, manufacturer and customer.
Since they have to be assessed in each case, the numerical data are not included in this document. General guidance on statistical assessment can be obtained from the references.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60812, Analysis techniques for system reliability — Procedure for failure mode and effects analysis (FMEA)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60812 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
3.1 Failure Mode and Effects Analysis
FMEA
method of reliability analysis intended to identify potential failures which have significant consequences affecting the system performance in the application considered
3.2 Design FMEA
FMEA (3.1) carried out by designers when developing the product
3.3 failure mode
effect by which a failure is observed in the bearing
3.4 failure effect
consequence of a failure mode (3.3) on the bearing system and equipment condition and operation
3.5 failure cause
deficiency or defect which causes a failure mode (3.3)
4 Common potential failure modes, effects and causes for half bearing shells
The connecting rod and main half bearing shells of a machine are only one part of an integrated system involving the lubricating oil, the lubrication system, the crankshaft, the engine block, the connecting rods and the half bearing shells themselves. Even the cylinder head material, bolt tightening and cylinder head gasket material have been known to influence bearing performance. Hence, any consideration of internal combustion engine bearing design shall include all elements of the system not just the half bearing shells. Table 1 gives a list of common potential bearing failure modes and the effects of bearing failure together with possible causes of failure. It is rare for failures to be encountered uniquely but rather they are found in combination such that the actual initial failure mode, and hence the causes, may be difficult to determine. Failure modes of the other bearing system components are not included.