BS 4084:1978

This standard BS 4084:1978 Specification for UNJ threads, with controlled root radius, for aerospace: inch series is classified in these ICS categories:

• 21.040.30 Special screw threads
• 49.030.10 Screw threads

Determines the basic triangular profile for inch series UNJ threads with controlled root radius. Gives a system of designating and also, for diameters from 0.060 in to 6 in, 3 series of diameter/pitch combinations and basic dimensions and tolerances. Also specifies the gauge procedures to be used. National appendix adds 20 UNJ constant pitch series for diameters up to and including 3 inches.