NPFC - FED-STD-H28/6
SCREW-THREAD STANDARDS FOR FEDERAL SERVICES SECTION 6 GAGES AND GAGING FOR UNIFIED SCREW THREADS-UN AND UNR THREAD FORMS
|Publication Date:||27 August 1991|
This section provides the standards for basic gaging principles, gaging practice, gage specifications, gage dimensions, gage measurements, measuring equipment, and calibration requirements for Unified inch screw threads (UN and UNR thread forms).
Information and requirements for gaging systems, their selection, and referee gaging used to determine product thread acceptability are found in FED-STD-H28/20 and are not repeated in this section.
This section applies to gages and measuring instruments used for inspection of product screw threads conforming to FED-STD-H28/20, and to their setting gages.
The following classes of gages are included in this section:
(1) Working gages - used during product manufacture.
(2) Inspection gages - used as final conformance gages in the acceptance of product.
(3) Setting gages - used for setting and for checking the above gages.