ISO 7146-1:2019 すべり軸受 — 金属流体軸受の損傷の外観と特性評価 — Part 1: 一般 | ページ 2

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, 1. In particular, the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, 2 (see www.iso.org/directives ).

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents ).

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This document was prepared by Technical Committee ISO/TC 123 Plain bearings, Subcommittee SC 2, Materials and lubricants, their properties, characteristics, test methods and testing conditions.

This second edition cancels and replaces the first edition (ISO 7146-1:2008), of which it constitutes a minor revision. The changes compared to the previous edition are as follows:

—Adjustment to the ISO Directives, including the replacement of"may" with"can" throughout.

A list of all parts in the ISO 7146 series can be found on the ISO website.

Introduction

In practice, damage to a bearing can often be the result of several mechanisms operating simultaneously. The complex combination of design, manufacture, assembly, operation, maintenance and possible reconditioning often causes difficulty in establishing the primary cause of damage.

In the event of extensive damage or destruction of the bearing, the evidence is likely to be lost, in which case it is impossible to identify how the damage came about.

In all cases, knowledge of the actual operating conditions of the assembly and the maintenance history is of the utmost importance.

The classification of bearing damage established in this document is based primarily upon the features visible on the running surfaces and elsewhere, and consideration of each aspect is needed for reliable determination of the cause of bearing damage.

Since more than one process can cause similar effects on the running surface, a description of appearance alone is occasionally inadequate in determining the cause of damage. Thus Clause 4 is subdivided into several subclauses including damage appearance and damage characteristics.

For the procedure of damage analysis, Clause 5 can be a helpful guide.

In Clauses 6 and 7, examples of all damage characteristics with typically associated damage appearance are given.

1 Scope

This document defines, describes and classifies the characteristics of damage occurring in service to hydrodynamically lubricated metallic plain bearings and journals. It assists in the understanding of the various characteristic forms of damage which can occur.

Consideration is restricted to damage characteristics which have a well-defined appearance and which can be attributed to particular damage causes with a high degree of certainty. Various appearances are illustrated with photographs and diagrams.

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.

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 4378-1, ISO 4378-2, ISO 4378-3, ISO 4378-4 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

Bibliography