TOOL FOR WORKING DEEP HOLES Russian patent published in 1995 - IPC

FIELD: metal cutting. SUBSTANCE: a tool is provided by the tubular insert 12, made of a material with temperature liner expansion factor, being more, than such factor of a material of the cutting head 2. One end of the tubular insert 12 is designed for engaging with the cutting head 2, its other end for engaging with a spring-loaded sleeve 4, mounted with possibility of an axial motion and restricted from rotation. The sleeve 4 has radial openings for feeding a cutting fluid, arranged in pairs with radial openings 10 for feeding the cutting fluid in the cutting head 2. Axis of the mentioned paired openings are parallel and they are arranged in lengthwise planes. Upon working of a blank by cutting the cutting plates 3, the cutting head and the tubular insert are being heated. The insert 12, being elongated upon heating, moves the sleeve 4, and then the openings 11 are being displaced relative to the openings 10, increasing a flow-through cross section for the cutting fluid. In the result a flowrate of the cutting fluid, being fed to the cutting zone, increases. Upon cooling the cutting head 2 by a flow of the cutting fluid the tubular insert 12, being cooled, became shorter. The spring 6 acts upon a bottom of the sleeve 4 and moves it. The openings 11 are being displaced relative to the openings 10, decreasing the flow-through cross section for the flow of the cutting fluid. EFFECT: enhanced quality of working deep holes. 1 cl, 1 dwg