THREAD KNURLING TOOL Russian patent published in 1997 - IPC

FIELD: plastic metal working, namely, tool for threading by plastic deformation. SUBSTANCE: tool includes movable and stationary threading dies. Each die has inlet and sizing parts. Inlet parts have different length values and different knurling angles. Total knurling angle along 0.4-0.6 of length of inlet part of stationary threading die is equal to 0 degree 36' - 0 degree 40'. Total knurling angle in zone of transition to sizing part of movable threading die is equal to knurling angle of inlet portion of stationary threading die being 0 degree 12'- 0 degree 14'. EFFECT: improved design. 2 dwg