METHOD FOR CUTTING DEAD THREADS BY MEANS OF COMB Russian patent published in 2003 - IPC

FIELD: tube making industry branch, namely working of tube couplings, coupling end portions of coupling-free tubes and locks of drilling pipes. SUBSTANCE: method for cutting dead threads by means of comb having taking and calibrating portions (length of calibrating portion is less than that of threaded portion) comprises steps of placing comb and arranging lines of recesses in parallel relative to generatrix of thread dents; at thread cutting process imparting rotation to part and imparting to comb axial feed by pitch of cut thread, crosswise feed according to slope of thread and additional radial motion; mounting comb in initial position at side of dead end of thread; selecting as reference point mostly distant in axial direction point of apex of closing calibrating tooth of comb; embedding selected point along thread axis by predetermined distance relative to plane for starting thread run-out. Additional radial motion is imparted to comb when the last moves according to its axial and crosswise feed values along path of reference point in range of above mentioned distance; value of additional radial motion is determined according to formula given in description of invention. EFFECT: enlarged using range of method. 4 cl, 1 dwg