[国外标准] BS 811-1950 Cycle threads
[国外标准] BS 4084-1996 UNJ threads, with controlled root radius, for aerospace. Inch series.
[国外标准] BS 21-1985 Pipe threads for tubes and fittings where pressure-tight joints are made on the threads
[国外标准] JIS B0204-1982 Screw Threads for Rigid Metal Conduits and Fittings