Abstract: A rod guide for maintaining a rod of a sucker rod string in substantially central position in a well tubing during reciprocal movement of the sucker rod string in the well tubing.

Abstract: A rod guide assembly having a mount rigidly molded on rod shank, a centralizer rotatably mounted on the mount having, closure means between the mount and the centralizer for preventing flow of particles into the centralizer.

Abstract: A guide for the rods of a rod string having a plurality of of units spaced longitudinally on the shank of the rod to provide a flex rod portion therebetween and a method of and apparatus for installing the guide unit on the shank.

Abstract: Corrosion control cathodic protection for the rod string and the well tubing. Anode assemblies for mounting on the rods of the rod string.

Abstract: A field-installable rod guide firmly grasps the sucker rod to which it is attached and reduces fluid friction to axial movement of the rod guide. The rod guide includes one or more channels for fluid to flow by the guide through straight or helical vanes. An axial access channel which permits application of the rod guide onto a sucker rod has a wide, tapered mouth to minimize the length of time during which the guide is stretched during installation. Recognizing that some stretch is inevitable in the guide at the point opposite the axial access channel, more rod guide material is placed at this point of greater stretch. In a preferred embodiment of the present invention, the rod guide stock from which the rod guide is machined is extruded to form the desired vanes as well as a non-circular "rod hole."This way, a "dual-radius" hole is enabled. The dual-radius hole narrows the gripping radius of the guide to solidly grasp the rod and eliminate slipping of the guide on the rod.

Abstract: A rod guide assembly having a mount moulded on the rod guide shank and a centralizer rotatably mounted on the mount and the method of installing the assembly on a rod guide shank.

Abstract: A stabilizer rod connectible in a sucker rod string of a sub-surface well pump having a shank of greater diameter than the shanks of the sucker rods of the string and connector means at its opposite ends whose diameter is not greater than that of the connector means at the ends of the sucker rods.

Abstract: A centralizer for a pump rod string which minimizes the resistance offered thereby to flow of well fluids therepast having a body provided with two pairs of longitudinally and circumferentially spaced radially outwardly extending ribs and a circumferential area of reduced external diameter between the two pairs of ribs providing a circumferential line of reduced mechanical strength to minimize likelihood of occurrence of longitudinal cracks in the body of the centralizer and minimizing flaking of the body when the body is subjected to strains and stresses due to bending of the rod, on which it is rigidly mounted, about axes substantially perpendiculer to the longitudinal axis of the rod and also providing flow passages of increased area between the two pairs of ribs.

Abstract: A centralizer for pump rod string which minimizes the resistance offered thereby to flow of well fluids therepast having two pairs of longitudinally and circumferentially spaced radially outwardly extending ribs.

Abstract: A rod guide assembly for rods of a sucker rod string having a pair of longitudinally spaced stops rigidly secured to the sucker rod and a plurality of independently movable guide body sections mounted on the rod between these stops for limited longitudinal movement between these stops.

Abstract: A well tool, such as a paraffin scraper or centralizer, installable on a rod of a pump rod string, which is composed of two longitudinal sections longitudinally movable relative to one another on a rod interposed therebetween into clamping locked position on the rod and a resilient longitudinal member compressed between one of the sections and the rod, the two sections having first co-engageable means for moving the two sections laterally relative to each other to compress the compressible member against the rod upon relative longitudinal movement of one section toward the other and a second co-engageable lock means for holding the two sections in longitudinally telescoped locked position on the rod.

Abstract: A guide for a sucker rod employed to actuate a pump connected in the tubing of a well whose body is formed of a resilient substance and adapted to resiliently grip the rod, the body having cam surfaces engageable with the rod for facilitating the mounting of the guide on the rod and arcuate internal stop surfaces at its opposite ends of substantially the same conformation as the surfaces of the enlargements or upsets at the opposite ends of the rod which the guide may engage if displaced on the rod as by contact with an internal obstruction in the tubing.

Abstract: A closure device connectible to a well head through which the polished rod of a rod string extends into a well tubing for operating pump means for moving well fluids to a surface flow conductor, the closure device having a tubular ram provided with a packing or plug for closing an annular passage between the polished rod and a tubular body connected to the well head above a lateral port of the tubular body, the tubular ram and the tubular body having thread means for moving the plug between an operative lower position wherein it closes the annular passage when the rod string is stationary and on inoperative upper position; seal means between the ram and the polished rod spaced above the plug; and a plurality of independent seal means between the ram and the tubular body operative when the plug is in its inoperative position.

Abstract: A well tool, such as a drilling pipe string, whose joints are provided with tubular protectors which are restrained against vertical movement on the joints while permitting rotation of the drilling pipe string relative thereto when the protectors engage the internal surfaces of a well bore or of a well casing through which the drilling pipe string extends.

Abstract: A sinker bar connectable to other sinker bars, sucker rods and the reciprocable operator of a down hole pump by use of conventional elevator and hoist connectors without the use of auxiliary devices such as pony sucker rods, the sinker bar having a reduced intermediate portion below the top portion thereof engageable by a conventional elevator connector and an external annular groove in the top portion constituting means engageable by a conventional hoist connector.

Abstract: A temperature control system, shown as a differential temperature control system, uses a special temperature sensor means. The temperature sensor means includes a resistance temperature responsive element that is paralleled by one or more temperature responsive switches that act as a limit, or are connected in series with an additional temperature responsive switch that also acts as a limit.

Abstract: A protector for well tools such as drill pipe tubing, and the like, which is positionable about a joint of a drill pipe or tubing and which is moved into pre-determined position on the box-half of a tool joint by the pin-half of the tool joint as it is moved into telescoped and threaded engagement with the box-half.