METHOD OF CHASING AND CHASER Russian patent published in 2012 - IPC B23G1/04 B23G5/02 

FIELD: process engineering.

SUBSTANCE: proposed method is intended for cutting internal thread at NC lathe with carbide plates in multiple passes in hollow cylindrical article from high-strength steel, for example, in rocket engine housing, and comprises controlling thread parameters, roughing and finishing by two-position cutting plates. Chasing in finishing passes is effected in the area of machine tool positive transverse coordinate by new cutting plate. After these passes, thread parameters are controlled to load chasing correction into tool control program. After chasing with correction, worn-out plate is fitted in second position of the cutter while new cutting plate is fitted at first position. Note here that chasing in the next articles is performed by worn-out plate in roughing passes with allowances for finishing and shifting the cutter in machine tool negative transverse coordinate zone with cutter shift for half the pitch backward. After roughing, cutter is moved back in to positive coordinate to proceed with finishing by new cutting plate. Cutter comprises holder with seat for said second carbide cutting plate. Note here that holder seats are arranged at one level at holder opposite sides while carbide plates are arranged axially symmetric and turned through 180° relative to each other.

EFFECT: higher process efficiency.

4 cl, 7 dwg