NPFC - FED-STD-H28/20
SCREW-THREAD STANDARDS FOR FEDERAL SERVICES SECTION 20 INSPECTION METHODS FOR ACCEPTABILITY OF UN, UNR, UNJ, M, AND MJ SCREW THREADS
|Publication Date:||10 March 1994|
This standard establishes the Federal Services' approved inspection and referee methods for inch and metric module (UN, UNR, UNJ, M and MJ) screw threads. The standard my also be applied for Class 5 interference fit threads.
The inspection method selected to specify product threads' acceptability for the Federal Services shall be in accordance with this standard.