Torque Standards for Fasteners

Standards for the torque-tension relationship in fasteners cover tests for determining it on both externally and internally threaded fasteners, tightening procedures, and quality control methods for those procedures, as well as laying out the interactions between all the applicable variables at play between different physical forces. Torque-tension relationship standards are available for both inch and metric series fasteners.

SAE AS 1310C-2024

Fastener Torque for Threaded Applications, Definitions Of

This SAE Aerospace Standard (AS) is intended for use by those involved in the design of aircraft, missile, or space systems, and their support equipment to define the various types of fastener torque.

ISO 16047:2005

Fasteners - Torque/clamp force testing

ISO 16047:2005 specifies the conditions for carrying out torque/clamp force tests on threaded fasteners and related parts. It is applicable, basically, to bolts, screws, studs and nuts made of carbon steel and alloy steel, whose mechanical properties are specified in ISO 898-1, ISO 898-2 or ISO 898-6, having ISO metric threads with thread sizes M3 to M39. It is also applicable to the combination of other externally and internally threaded fasteners with a triangular ISO thread according to ISO 68. It is not applicable to set screws and similar threaded fasteners that are not under tensile stresses, nor to screws which form their own mating thread or threaded fasteners having additional self-locking features.

IFI-143:2002

Test for Evaluating the Torque-Tension Relationship on Both Externally and Internally Threaded Fasteners

This standard provides a test method for determining the torque-tension relationship on both external and internal threaded fasteners for the purpose of measuring the frictional characteristics of the threaded fasteners.

IFI-543:1999

Test for Evaluating the Torque-Tension Relationship on Both External and Internal Metric Threaded Fasteners

This standard provides a test method for determining the torque-tension relationship on both external and internal threaded fasteners for the purpose of measuring the frictional characteristics of the threaded fasteners.

SAE AIR 1471B-2018

Torque Tightening Threaded Fasteners

The purpose of this SAE Aerospace Information Report (AIR) is to provide the aerospace propulsion industry with recommended assembly torque limits for commonly used aircraft propulsion system threaded fasteners when a common torque value per size is the objective.

SAE J 1701-2017

Torque-Tension Tightening for Inch Series Fasteners

This SAE Information Report is provided as an advisory guide. Individual application discretion is recommended. The content has been presented as accurately as possible, but responsibility for its application lies with the user. The document covers the variables in the torque-tension relationship: friction, materials, temperature, humidity, fastener and mating part finishes, surfaces, and the kind of wrenching employed. Also, described in this document is the torque management required to achieve correct fastener joint tightening. The thread fit of fasteners must be in accordance with Class 2A for external and Class 2B for internal inch threads.

SAE J 1701M-2022

Torque-Tension Tightening for Metric Series Fasteners

This SAE Information Report is provided as an advisory guide. Individual application discretion is recommended. The content has been presented as accurately as possible, but responsibility for its application lies with the user. The document covers a number of the variables in the torque-tension relationship: friction, materials, temperature, humidity, fastener and mating part finishes, surfaces, and the kind of tightening tools or equipment used. Also described in this document is the torque management required to achieve satisfactory fastened joint tightening. This guide is limited in application to clearance fit threads, such as the common 6g/6H class of fit. Other thread types including interference fit, mechanical locking, prevailing torque, or forms other than ISO-metric may apply to some aspects of this standard but are not specifically covered. The procedures described in this document are based on general factors for the determination of the torque-tension relationship for the use of end users. This is a guide and is not intended to be made a procurement requirement. For critical joint design, the assembly torque values should be determined by experimentation using the exact assembly components.

SAE J 174-2013 (SAE J174-2013)

Torque-Tension Test Procedure for Steel Threaded Fasteners~Inch Series

This test procedure is intended to provide a quality control method for checking torque-tension characteristics of non-prevailing torque type threaded steel fasteners 1/4 through 1 in nomial diameters. Realistically, torque-tension relationships for specific individual fastener assembly joints will vary due to the different joint parameters. Tests using actual joint components will be required to determine accurate torque-tension values for those conditions. For the metric version, see SAE J174M.

SAE J 174-2019

Torque-Tension Test Procedure for Steel Threaded Fasteners - Inch Series

This test procedure is intended to provide a quality control method for checking torque-tension characteristics of non-prevailing torque type threaded steel fasteners 1/4 through 1 in nominal diameters. Realistically, torque-tension relationships for specific individual fastener assembly joints will vary due to the different joint parameters. Tests using actual joint components will be required to determine accurate torque-tension values for those conditions. For the metric version, see SAE J174M.

ISO 5347-16:1993

Methods for the calibration of vibration and shock pick-ups - Part 16: Testing of mounting torque sensitivity

Lays down detailed specifications for the instrumentation and procedure to be used for mounting torque sensitivity testing. Applies to pick-ups mounted by screws, bolts or other threaded fasteners. The change in calibration factor due to the mounting torque is determined. Is applicable for a mounting torque range of one-half of the specified value, the specified value und twice the value of the specified mounting torque.

SAE ARP 600C-2023

Torque Determination, Method of, For Tube or Hose End Fitting Connections, Flared, Flareless, or Miscellaneous Screw Thread Style

This SAE Aerospace Recommended Practice (ARP) defines a method for determining a torque value (range) for threaded fluid connections.