ISO TR 1281-2-2008 cor1-2009 PDF

Full title and description

ISO/TR 1281-2:2008/Cor 1:2009 — Rolling bearings — Explanatory notes on ISO 281 — Part 2: Modified rating life calculation, based on a systems approach to fatigue stresses — Corrigendum (technical correction) 1. This corrigendum (Cor 1:2009) applies to ISO/TR 1281-2:2008 and contains the technical corrections to the original 2008 technical report.

Abstract

ISO/TR 1281-2:2008 provides explanatory background for ISO 281’s modified rating-life calculation that introduces life-modification factors (notably a1 for reliability and aISO for a systems approach). The report explains the derivation and application of these factors in the modified rating-life equation L_nm = a1 · aISO · L10 and gives background on modelling fatigue stresses and life integrals used to quantify effects such as contamination and lubrication. The Cor 1:2009 document issues technical corrections to the 2008 text.

General information

• Status: Published (corrigendum applied to ISO/TR 1281-2:2008).
• Publication date: Original TR published December 2008; Corrigendum (Cor 1) published October 2009 (Corr. 1:2009).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 21.100.20 — Rolling bearings.
• Edition / version: Edition 1 (ISO/TR 1281-2:2008) with Corrigendum 1 issued 2009 (ISO/TR 1281-2:2008/Cor 1:2009).
• Number of pages: Original technical report: 47 pages; Corrigendum: 3 pages.

Scope

This corrigendum corrects technical items in ISO/TR 1281-2:2008, a technical report that supplies explanatory notes and background for the modified rating-life calculation used with ISO 281. The underlying TR (Part 2) addresses how to quantify system-level fatigue effects and how to evaluate the modification factors (aISO and related terms) used to produce a modified basic rating life for rolling bearings under non-ideal service conditions.

Key topics and requirements

• Definition and derivation of life-modification factors used in the modified rating-life equation (a1 for reliability and aISO for systems approach).
• Modified rating-life equation L_nm = a1 · aISO · L10 and guidance on applying the factors.
• Discussion of fatigue-stress modelling and life integrals (including Ioannides–Harris approaches) to quantify contamination, lubrication and surface damage effects.
• Guidance on assessing contamination and lubrication factors, and on comparing ‘smooth’ versus ‘dented’ contact life contributions.
• Technical corrections introduced by Corrigendum 1 to clarify or correct equations, definitions or numerical examples in the 2008 TR.

Typical use and users

Used by bearing designers, mechanical and reliability engineers, tribologists, test laboratories, maintenance planners and standards committees to interpret and apply the modified rating-life methodology in ISO 281. Practitioners use the guidance when assessing bearing life under contaminated, lubricated or otherwise non-ideal system conditions and when comparing design or maintenance options that affect fatigue stresses.

Related standards

Directly related to ISO 281 (Bearings — Basic dynamic loads and rating life), and to other parts of the ISO/TR 1281 series (Part 1 and Part 2) that give explanatory notes on ISO 281. Users commonly consult ISO/TR 1281-2 alongside ISO 281:2007 (and any later revisions) as well as related rolling-bearing standards and dimensional/tolerance standards used in bearing design and testing.

Keywords

rolling bearings; rating life; modified rating life; life-modification factor; aISO; a1; fatigue stresses; Ioannides–Harris integral; contamination factor; lubrication factor; ISO 281; corrigendum.

FAQ

Q: What is this standard?

A: It is a technical report (ISO/TR 1281-2:2008) that explains and provides background for the modified bearing rating-life calculation in ISO 281; the item titled ISO/TR 1281-2:2008/Cor 1:2009 is the technical corrigendum (Cor 1) that corrects specific parts of the 2008 TR.

Q: What does it cover?

A: It covers derivation and application of life-modification factors (including a1 and aISO), the modified rating-life formula L_nm = a1 · aISO · L10, and methods for quantifying system-level fatigue effects such as contamination and lubrication impacts; the corrigendum fixes technical errors in the published 2008 text.

Q: Who typically uses it?

A: Bearing designers, reliability and mechanical engineers, tribologists, testing laboratories, maintenance planners and standards developers who must evaluate or specify bearing life under realistic service conditions.

Q: Is it current or superseded?

A: The document status on ISO records shows the TR published in 2008 with Corrigendum 1 issued in 2009; the corrigendum is an amendment that corrects the 2008 edition. Users should confirm any later revisions or newer editions of ISO 281 or ISO/TR 1281 parts for the absolute latest status before relying on the text in critical applications.

Q: Is it part of a series?

A: Yes — ISO/TR 1281 is a set of explanatory parts addressing ISO 281; this item is Part 2 (modified rating-life calculation) and exists alongside other explanatory parts and the main ISO 281 standard that defines basic rating-life and load parameters.

Q: What are the key keywords?

A: rolling bearings; modified rating life; life-modification factor; aISO; a1; L10; fatigue stresses; Ioannides–Harris; contamination factor; lubrication factor.