This standard stipulates the internal thread for installing wire thread inserts? When the wire thread inserts made by B5513-80 and HB5514-80 are installed into the internal thread specified in this standard, the screw hole formed shall comply with HB241-75 ordinary thread coarse thread 2 Level, fine tooth 2a level accuracy.
HB 5515-1980 history
1996HB 5515-1996 Internal thread for installing wire nut