GUIDE BUSH Russian patent published in 1998 - IPC

FIELD: mechanical engineering. SUBSTANCE: this relates to tooling used for accurate direction of cutting tool such as drills in drilling and/or treating of deep holes. Guide bush has body and replaceable insert located in it in the form of hollow cylinder. Replaceable insert is of increased length which is equal to 0.5-1.0 of initial length of working part of tool being used, but not more than 30 mm which allows for improving operating qualities of guide bush due to more rigidity in tightness of connection. Replaceable insert in its working end has circular supporting surface of 2.0-2.5 mm width of its inner diameter. Remaining part of end surface and end surface of body have common tapered surface with angle at top of cone up to 175 deg. EFFECT: higher efficiency. 1 cl, 2 dwg