Abstract: A drill string is made flexible near the lower marginal end thereof, and a pneumatic turbine motor is located at the lower terminal end thereof. The pneumatic turbine is connected to a planetary gear reduction system for rotating a drill bit. The diameter and the length of the pneumatic turbine motor, gear reduction system, and bit is of a size which enables the entire assembly to negotiate a sharp bend in the borehole, so that the borehole can be formed to extend downwardly along a relatively straight vertical line towards a payzone, where the borehole then sharply bends laterally towards the payzone, and then continues in another relatively straight line horizontally through the payzone. The pneumatic turbine motor includes reaction ports arranged to force the drill bit against the formation being penetrated, and to counteract the bit torque.

Abstract: In a borehole forming operation, the flow of gas through a downhole pneumatic motor is regulated to eliminate horsepower variations due to variations in bottom hole pressure. The pneumatic motor is connected to the lower end of a tubing string and an orifice is placed within the entrance and exit gas passageways leading to and from the pneumatic motor. The uphole source (i.e., compressors) of gas pressure and gas flow rate is maintained as a constant value which assures that sonic flow conditions exist at the lower orifice. The employment of gauged orifices placed within the inlet and exit passageways of the gas motor assures that sonic flow conditions exist at the lower orifice and as the bottom hole pressure varies, there is no resultant change in the motor output horsepower since constant flow rate and pressure drop ratio through the motor is maintained. This is the case so long as the bottom hole pressure does not increase to the critical ratio.

Abstract: This invention relates to a downhole rotary drilling device. More particularly, it relates to a gas operated turbine motor designed to be located downhole adjacent a rotary drilling bit to impart rotational force to the drilling bit and thus accomplish subsurface drilling operations.

Abstract: Apparatus by which a vertical borehole is curved to a new angle and extended through a production reservoir. A vertical borehole of a suitable diameter is extended downhole to the proximate depth of the production reservoir. A Zublin drill guide apparatus is employed to drill a curved section of the hole, thereby turning the borehole to a desired angle so that the lower marginal end of the borehole is directed laterally away from the vertical part of the borehole. A drill pipe string is positioned within the vertical part of the borehole. A flexible pipe is fitted to the downhole end of the drill pipe string, and a Zublin straight drill guide assembly is fitted to the end of the flexible pipe. A motor, such as an expansible gas turbine motor, for example, is connected to the end of the straight drill guide assembly. A suitable drill bit is connected to be rotated by the turbine motor.

Abstract: A tool for housing a magnetic directional survey instrument for inserting the instrument into a deviated well bore. Means are provided on the tool for circulating well fluids past the tool while it is in the well bore. There is provided means, connectable on the tool, for centering the tool in the vertical, as well as the deviated portion of a well bore.

Abstract: A guide for drilling a straight section of a bore hole deflected from the vertical. The apparatus comprises either a normally straight or a curved-straight tubular member which has a plurality of generally circumferential cuts disposed along the length of the guide. The cuts allow the guide to be bent sufficiently to enter and traverse a short radius curve and then return to its normal configuration for guiding the drilling of the straight portion of the deflected bore hole. A clutch mechanism disposed in the drill guide permits engagement of the guide by the drill string for orientation of the guide.

Abstract: Method and apparatus by which a vertical borehole is curved to a new angle and extended through a production reservoir. A vertical borehole of a suitable diameter is extended downhole to the proximate depth of the production reservoir. A Zublin drill guide apparatus is employed to drill a curved section of the hole, thereby turning the borehole to a desired angle so that the lower marginal end of the borehole is directed laterally away from the vertical part of the borehole. A drill pipe string is positioned within the vertical part of the borehole. A flexible pipe is fitted to the downhole end of the drill pipe string, and a Zublin straight drill guide assembly is fitted to the end of the flexible pipe. A motor, such as an expansible gas turbine motor, for example, is connected to the end of the straight drill guide assembly. A suitable drill bit is connected to be rotated by the turbine motor.

Abstract: A flexible pipe adapted for connection in a drill string, having sufficient wall thickness in order to withstand forces imposed by drilling a well. The flexible pipe has a plurality of improved, essentially circumferential cuts, each cut being through the wall thickness of the pipe. The cuts provide a pipe having a plurality of dovetail teeth and complimentary recesses on each end of the intermediate segments. The teeth on one segment are positioned in the recesses and interlocking with the teeth of the adjacent segment. Each side of each tooth consists of two reversed, intersecting semicircles. The tooth and recess interlock has sufficient clearance to form a joint which has limited relative movement in any direction between the segments.

Abstract: Mineral values are recovered from underground formations, and pollution of the formation is substantially diminished if not eliminated, by determining the geometry of an ore body and thereafter isolating the body by the formation of an impermeable barrier thereabout which has the capability of retaining leaching fluid therewithin. Leaching fluid remains downhole without substantial dilution by formation fluid, and conversely without pollution of the surrounding formation, until the mineral values are chemically changed into a recoverable substance which is subsequently pumped to the surface of the earth. In one embodiment of the invention, uranium values are recovered by the use of an organic extractant liquid admixed with an acid aqueous leaching fluid by homogenizing the two solutions prior to pumping the mixture downhole into contact with the ore deposit.