GB176048A - Improvements in or relating to well-boring drills - Google Patents

Abstract

176,048. Reed, C. E. Oct. 25, 1920. Bore-hole apparatus.-In a wellboring drill, a sleeve 42, Fig. 1, is arranged coaxially within the drill stem 31 and forms the passage for flushing-water while the surrounding annular chamber 47 forms a lubricant-chamber, the flushing-water acting through a piston 49 to force the lubricant to the bearings of rolling cutters. The passage of lubricant may be controlled by a, device comprising an apertured member 60, Fig. 5, fixed to the sleeve 42 and a movable apertured disc 62 adapted to be fixed in adjusted position by screws. The apparatus shown comprises a drill head 1 threaded to a reamer block 17 which is threaded to the sleeve 42 and is connected bv a sleeve 33 to the drill stem 31. The reamer block has spaced pockets 22 in which rolling sectional reaming cutters 18 are carried by hollow spindles 24 to which lubricant is supplied through passages 40 for delivery through ports 37 to the cutters 18 ; flushing-water is supplied to the pockets through ports 23. The drill head comprises a central pocket e enclosed by walls n, o and containing rolling cutters 5 mounted on a hollow cross spindle 6. while lateral pockets enclosed by walls c, d contain rolling side cutters 2, 3 mounted on hollow spindles 4 which are inserted from the central pocket e and are preferably held by a brace j carried by the spindle 6. A. lubricant-chamber 8 in the drill head supplies lubricant through the hollow spindles 4, 6 to the cutters 2. 3, 5 and is itself supplied with lubricant either directlv from the annular reservoir 47 or indirectly through the hollow spindles 24 of the reaming cutters 18. Water is supplied to the drill head through ports 10, its passage through the lateral pockets thereof being limited by washers b carried by the spindles 4; external return passages In are provided for the water. All the cutters spindles have eccentric heads to prevent rotation.