GB265274A - Rotary deep well drilling apparatus - Google Patents

Abstract

265,274. Reed, C. E. Nov. 2, 1925. Borehole apparatus.-A well-boring drill comprises a head 1 with a core-opening 2, projections 4, 4<a>, Fig. 2, round the head, and a central portion 5 surrounding the core opening. As shown in Figs. 1 and 2, the bit head 1 has on its lower face three unequally spaced inclined recesses 3 receiving rolling side cutters, and two recesses 17 receiving rolling bottom cutters 16, the recesses 3, 17 merging together and forming a channel for the flushing- fluid, which is directed through ports 3<x>. The side cutters are supported on stepped bearing pins 7 the larger ends of which have flattened sides; the ends of the pins 7 slide into grooves 10, 14 at the sides of the recesses 3 to contact with shoulders 10<a>, 14<a> in the grooves, the pins 7 being then locked by screws 15. The bottom cutters 16 are of different widths and are carried on pins 21 which are unsupported at their inner ends and have at their outer ends eccentric heads held by screws; washers 22 and bearing plates 18 sliding into grooves assist in supporting the pins 21, the plates 18 of the two recesses 17 being at different radial distances. The bit head is threaded to a reamer block 46 and contains a core tube 27 with a removable shoe 28 which is perforated to admit flushing water to the core; a pivoted core-trap 31 is provided!. In lateral recesses of the reamer block 46 are arranged cages 45 rigidly held by a tube 56 and an upper sleeve 47; the ends of the cages seat bearing members 49, 50 supporting reaming cutters 44, the upper bearing members being locked by a plug 52. Specifications 265,504 and 265,507 are referred to.