ISO 8642-2008 PDF

Full title and description

Aerospace — Self-locking nuts with maximum operating temperature greater than 425 °C — Test methods. This International Standard specifies the test devices and test methods for metric self-locking nuts with MJ threads intended for aerospace applications where the maximum operating temperature exceeds 425 °C; it is intended to be used together with the corresponding procurement specification (ISO 8641).

Abstract

ISO 8642:2008 defines the apparatus, procedures and acceptance-related test methods for high‑temperature self‑locking nuts (MJ thread) used in aerospace construction. The document describes each test and the required test device so that test results are reproducible and comparable between laboratories; it is to be used in conjunction with ISO 8641 (procurement specification).

General information

• Status: Withdrawn / superseded (replaced by a later edition published 2025).
• Publication date: 2008 (published 26 August 2008; often listed as Sept 2008).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 49.030.30 (Nuts / fasteners for aerospace).
• Edition / version: Edition 2 (2008).
• Number of pages: 20 pages (typical listing on standards catalogues).

Scope

Applies to metric self‑locking nuts with MJ threads intended for use in aerospace structures where maximum operating temperature is greater than 425 °C. The standard specifies the test device and the method for each test, and it is applicable when dimensional, procurement or product documents refer to this International Standard. Alternative test devices or methods may be used, but in the event of dispute the procedures in ISO 8642 take precedence; ISO 8642 is intended to be used in conjunction with ISO 8641.

Key topics and requirements

• Definition and description of the test apparatus required for high‑temperature performance testing of self‑locking nuts.
• Step‑by‑step test procedures for evaluating locking performance, torque retention and other functional characteristics at temperatures >425 °C.
• Requirements for sample preparation, test conditions, and reporting to ensure repeatability and comparability.
• Statement that the standard is to be used alongside ISO 8641 (procurement specification) and that it governs in cases of dispute.

Typical use and users

Used by aerospace fastener manufacturers, test laboratories, OEM qualification and procurement engineers, quality assurance and conformity assessment bodies, and engineering teams responsible for selecting or approving high‑temperature self‑locking nuts. Typical activities include type testing, acceptance testing, supplier qualification, and product verification against procurement documents that reference ISO 8642.

Related standards

Primary related document: ISO 8641 (Aerospace — Self‑locking nuts with maximum operating temperature greater than 425 °C — Procurement specification). ISO 8642:2008 has been superseded by a later edition (ISO 8642:2025), which is the current published version of the test‑methods standard. Other related fastener and thread standards (for dimensional, material and mechanical property requirements) are typically used alongside these documents in procurement and testing.

Keywords

self‑locking nut, MJ thread, aerospace fastener, high temperature (425 °C), test methods, ISO 8641, nut testing, fastener qualification, procurement specification.

FAQ

Q: What is this standard?

A: ISO 8642:2008 is an International Standard that specifies test devices and test methods for metric self‑locking nuts with MJ threads intended for aerospace use at temperatures above 425 °C.

Q: What does it cover?

A: It covers the description of the test equipment and detailed procedures for each test (sample preparation, test conditions, measurement and reporting) needed to assess locking performance and related characteristics of the specified nuts at high temperatures. It is intended to be used together with ISO 8641 (procurement specification).

Q: Who typically uses it?

A: Aerospace fastener manufacturers, independent test laboratories, OEMs and procurement/quality engineers use the standard for supplier qualification, type testing and acceptance testing of self‑locking nuts intended for high‑temperature service.

Q: Is it current or superseded?

A: ISO 8642:2008 has been withdrawn and superseded by a later edition; the test methods standard was republished as ISO 8642:2025 (the 2025 edition is the current published version). Users should refer to the 2025 edition for the latest requirements.

Q: Is it part of a series?

A: Yes — ISO 8642 (test methods) is part of a set of documents addressing high‑temperature self‑locking nuts; ISO 8641 provides the procurement specification that complements the test methods in ISO 8642. Together these form the core ISO guidance for this class of aerospace fasteners.

Q: What are the key keywords?

A: Self‑locking nut, MJ thread, aerospace, high temperature, test methods, ISO 8641, fastener testing, qualification.