SAE AS 28431:2003 pdf download

SAE AS 28431:2003 pdf download Aerospace Signaling Torque Wrenches
1. SCOPE AND CLASSIFICATION:
1.1 Scope:
This Society of Automotive Engineers (SAE) Aerospace Standard covers requirements for micrometer adjustable, feel impulse, torque wrenches. The torque wrench is used to apply a pre-set torque to threaded fasteners and other torque requirements.
1.2 Classification:
Torque wrenches covered by this specification shall be one of the following types and classifications, as specified.
Type I Bi-directional torque wrench
Class 1 Non-ratchet head (precise clockwise torque)
Class 2 Ratchet head (precise clockwise torque)
Class 3 Non-ratchet head (precise counter-clockwise torque)
Class 4 Ratchet head (precise counter-clockwise torque)
Class 5 Changeable head (precise clockwise torque)
Class 6 Changeable head (precise counter-clockwise torque)
Type II Uni-directional torque wrench
Class 1 Non-ratchet head (precise clockwise torque)
Class 2 Ratchet head (precise clockwise torque)
Class 3 Non-ratchet head (precise counter-clockwise torque)
Class 4 Ratchet head (precise counter-clockwise torque)
Class 5 Changeable head (precise clockwise torque)
Class 6 Changeable head (precise counter-clockwise torque)
1.2.1 Class Accuracy: Type I bi-directional torque wrenches shall have an accuracy of ±4% in the precise torque direction, and ±6% in the opposite direction. Type II uni-directional torque wrenches shall have an accuracy of ±4% in the precise torque direction, and shall not signal in the opposite direction.
1.2.2 Accuracy: Torque accuracy is defined as the difference between the applied torque and the preset torque divided by the pre-set torque expressed as a percentage.
2. APPLICABLE DOCUMENTS:
2.1 The following documents form a part of this standard to the extent specified herein. Where conflicts occur between this standard, and specified documents, this standard shall take precedence.
2.1.1 SAE Publications: Available from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001.
AS4984 Coating Requirements for Aerospace Hand Tools
2.1.2 ASTM Publications: Available from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.
ASTM E 18 Rockwell Hardness and Rockwell Superficial Hardness of Metallic Materials,Standards Methods of Test for
2.1.3 ASME Publications: Available from ASME, 22 Law Drive, Box 2900, Fairfield, NJ 07007-2900.
ASME B107.4 Driving and Spindle Ends for Portable Hand, Air, and Electric Tools
ASME B107.10M Handles and Attachments for Hand Socket Wrenches – Inch and Metric Series
ASME B107.17M Gages, Wrench Openings, Reference
3. REQUIREMENTS:
3.1 Torque Wrench:
The torque wrench shall have an accurate micrometer-type, presetting mechanism upon which the required torque can be hand set by adjusting the mechanism. The torque wrench shall have a locking mechanism which holds the pre-set torque securely during use of the torque wrench. Operation of the pre-setting mechanism and locking mechanism shall not require the use of tools or equipment. The torque wrench shall have a torque signaling device that meets the requirements of 3.3.7.
3.2 Illustrations:
The illustrations herein are descriptive and are not intended to preclude the purchase of torque wrenches otherwise conforming to this specification.