NPFC - FED-STD-H28
SCREW-THREAD STANDARDS FOR FEDERAL SERVICES
|Publication Date:||12 March 1990|
This standard establishes complete dimensional data requirements for screw threads including, as necessary, recommendations on gages, dies and taps and other items associated with the purchase/use of interchangeable threaded parts by Federal Government Agencies. So far as practicable, these data are intended to conform to generally accepted commercial practice, although certain special requirements of the Federal Services necessitate the inclusion of some standards not generally applicable outside the Government. References are cited throughout the text to the standards promulgated by The American Standards Association (ASA) and the United States of America Standards Institute (USASI), now called The American National Standards Institute (ANSI) and to such other published standards as are in agreement with the specifications herein.
This standard includes the basic dimensional requirements for assembly, interchangeability, tensile strength, shear strength, fatigue strength and installation and removal torque of threaded products. Specific requirements for particular Screw-Thread Standards are covered by the Detail Standards (see Para 3). Supplements to the Detail Standards are covered in the Appendix of this document. (See Para 4).