GB1184970A - Flexible Drill String and Operating Apparatus therefor - Google Patents

Abstract

1,184,970. Hose reel. NORTHROP CORP. 15 Oct., 1968, No. 48787/68. Heading B8M. [Also in Division E1] Drilling equipment, for use for example on the moon, includes a drum 16, a drill string comprising a flexible hose 17 normally wound around a helical groove 24 formed in the outer surface of the drum, the flexible hose having circumferential ridges formed in its outer surface to mate with transverse depressions 26 in the helical groove, and a plurality of longitudinallyextending passageways being provided in the flexible hose into which pressurized fluid can be pumped to operate a drill tool and to stiffen the flexible hose during drilling operations. One end of the string is attached to a chamber 18 positioned inside the drum and provided with a compressor to pump the fluid-for example an inert gas-to the drill tool at the other end of the string. The fluid passes down an inner conduit in the string and returns from the tool up the annulus between the inner and outer conduits. The inner conduit may be formed of polytetrafluoroethylene and spaced by radial ribs from the outer conduit which is formed of braided wire and covered with rubber. Roller 37 slidable on rod 34 guides the string on and off the drum. The string passes through an aperture in member 38 provided with a projection mating with a longitudinal groove 33 in the string to stop the string from rotating. The drum is rotated by electric motor 19 and may be mounted on an arm secured to the space vehicle. Core samples may be collected in a split and hinged tube placed around the string and coupled by a flexible bellows-like coupling to the surface casing installed in the top of the hole being drilled.