Abstract: An intermediate weight drill stem member having a tool joint or end with at least one reduced diameter surface for hoisting and handling protected by an enlarged diameter wear protecting length on either side thereof and providing at its junction end with the tubular body a straight-wall surface, a length having a diameter less than the maximum diameter of the adjacent enlarged length, for welding to a straight-wall length of the contiguous externally upset end of the tubular body. The tubular body is preferably about twenty feet long compared to a combined length of ten feet for the two tool joints, thereby eliminating a need for an intermediate wear protector length along the tubular body length.

Abstract: There is disclosed a control system for a hydraulic down-hole earth drilling motor of the helical gear pair type to control the pressure drop of the fluid through the motor so that it does not become excessive. A housing is provided defining a chamber, one end of the housing being secured to the outer member housing of the motor. Valve means and pressure controlling means are positioned in the chamber. Linkage means positioned within the chamber joins the valve means pressure controlling means and the upper end of the inner member of the motor. In operation the inner member of the motor may be caused to operate the valve means to control the fluid flow and therefore the pressure drop through the motor in order to protect the motor from overload. A further embodiment of the invention corrects an additional problem in down-hole motors resulting from the back flow when the drilling is stopped for any reason.

Abstract: A sealed bearing system for rotatably journaling a shaft relative to a surrounding housing by means of bearing assemblies each comprising a pocket secured to the housing and a bearing support secured to the shaft, the bearing support extending into the pocket with bearings interposed between the bearing support and the walls of the pocket; a lubricant is sealed in the pocket by sealing rings extending between the bearing support and the walls of the pocket; the bearing assemblies are provided in opposing pairs with flow restrictor means lying between the bearing assemblies, thereby forming a system which permits fluid flow between the shaft and the housing but which seals the bearings from infiltration of the fluid irrespective of pressure variation in the flowing fluid.

Abstract: There is disclosed a transmission between an orbiting element and an element rotating on its own centers. It is disclosed particularly in connection with a motor operating on the Moineau principle and the invention replaces the conventional connecting rod with double universal joints and it also can modify the ball and tube arrangement disclosed in earlier patents.

Abstract: Earth drilling hydraulic shock absorber having an anvil reciprocally mounted in a casing and operatively connected with a plurality of independently operating pistons, the anvil being reciprocally mounted within the casing through a spline connection with unidirectional sealing means for equalizing pressure across the sealing means with the hydrostatic pressure in a borehole for retaining a lubricating fluid around the spline connection and to prevent abrasive matter in drilling fluid from coming in contact with the spline connection. The anvil of the shock absorber may include a reduced effective pressure area so that the anvil engages the first piston at a lower downweight.