GB222822A - Drilling mechanism for boring wells and the like - Google Patents

Abstract

222,822. Wilson, J. R., Matlock, C. C., Berry, R. S., and Malloy, H. Oct. 3, 1923, [Convention date]. Bore-hole apparatus; shaft-sinking by boring. - Means for drilling large wells or bore-holes, sinking shafts &c. comprises a rotating tubular stem 15 conveying liquid to flush the bore-hole, a head 33 carrying cutters 37 and fluid-pressure operated hammer pistons 42 for operating the cutters, and concentric pipes 31, 32 conveying actuating fluid, such as compressed air, respectively to and from the valve gear controlling the hammer pistons; by lowering a fishing tool into engagement with a collar 34 on the head, the latter may be raised independently of the stem 15. During such lifting, spirally toothed segments 39, splined to the spring-pressed shanks 38 of the cutters 37, co-operate with spirally toothed ribs 20 on the stem 15, whereby the cutters 37, which are radially arranged when in operative position, are turned into tangential arrangement to permit them to pass the stem &c. When the head 33 is in its lowest position, collars 35 thereon engage recesses in the end plate 17 of the stem to hold the parts against relative rotation; the end plate 17 carries cutters 66 to remove the central core of the bore. Water passes from the stem 15 through ports 58, Fig. 9, to act on plungers 57 and thereby force grease from chambers 55 through ports 56 into chambers 57 surrounding the shanks 38 of the cutters to lubricate the latter. When the head 33 is raised, a spring-pressed sleeve 50 therein moves downwardly to close the ports 58 and the ports leading to the hammer-piston mechanism; simultaneously, a spring-pressed sleeve 25 on the stem 15 moves upwardly to close the ports communicating with the fluid supply and exhaust pipes 31, 32. Chambers 62, Fig. 12, with removable plugs 63, are provided in the head 33 and communicate with exhaust passages 47 leading from the piston hammer mechanisms to catch water deposited therein. The head 33 is built of annular sections A, B, C, D, connected by bolts 64, 65, to facilitate assemblage.