Abstract: An active counterbalance for suspending a power swivel from a traveling block. The power swivel includes a motor drive assembly for rotating a drill string and a handling system for supporting a drill pipe. The counterbalance includes a motor which provides means for biasing the load capacity of the counterbalance when supporting the power swivel to allow vertical displacement of the power swivel relative to the traveling block. The counterbalance prevents damage to connecting or sealing surfaces when adding pipe to or removing pipe from the drill string because most of the weight of the power swivel and pipe suspending from the handling system is transferred to the counterbalance.

Abstract: Producing one-side zinc electroplated strip having enhanced phosphating characteristics. Prior to electroplating, the non-electroplated side of the steel strip is cathodically pickled. Cathodic pickling minimizes staining and etching to the non-electroplated strip surface by the zinc electrolyte during electroplating of the opposite strip surface.

Abstract: A fail-safe gate valve assembly having a power actuator and a spring actuator disposed on opposite sides of a flowline. The assembly includes a valve body, a valve chamber including a gate movable between open and closed positions for controlling fluids through the flowline, a first housing containing the power actuator disposed on one side of the valve body and a second housing containing the spring actuator disposed on the opposite side of the valve body. The power actuator urges the gate from one to another of the positions. The spring actuator urges the gate from the other to the one of the positions in event a power loss occurs to the power actuator. The spring actuator may include an override thereby allowing the override to be used to open and close the gate valve without compressing the springs.

Abstract: A top driven driling unit including a motor drive assembly for rotating a drill string and a handling system for supporting the drill string. The motor drive assembly includes a drill motor, a swivel bearing for supporting the load of the drill string during drilling and a sub assembly for connecting the drill motor to the drill string. The handling system includes a housing for supporting the swivel bearing, a handling ring, a stem for supporting the load of the drill string during tripping, an elevator, elevator links for supporting the elevator from the handling ring, a traveling block, and support links for supporting the housing from the traveling block. The structural relationship between the handling ring, the stem, and the housing provides an alternative load path for elevator loads during tripping or when running well casing liner that bypasses the swivel bearing.

Abstract: Producing one-side zinc electroplated strip having enhanced phosphating characteristics. Prior to electroplating, the non-electroplated side of the steel strip is cathodically pickled. Cathodic pickling minimizes staining and etching to the non-electroplated strip surface by the zinc electrolyte during electroplating of the opposite strip surface.

Abstract: A culvert having a corrosion resistant composite coating and a method of producing the corrosion resistant composite coating. The coating method is for use in a coventional hot dip coating line of the type wherein a steel strip, having been appropriately pretreated so as to be at or above the coating temperature and have its surface free of oxides, is caused to pass through a bath of molten coating metal. A fibrous aramid paper is bonded to the surface of the steel strip by pressing the fibers into the molten coating layer immediately after the steel strip exits the coating bath. The steel strip may be fabricated into construction products such as culvert which may be further protected with bituminous type coatings.

Abstract: A sub assembly for connecting a power swivel to a drill string. The assembly includes a telescopic sub having a preloaded spring. The telescopic sub has three discrete positions enabling it to travel in either direction from a normal position. This capability prevents thread damage for both when connecting and disconnecting a drill pipe to the drill string.

Abstract: Apparatus and method for controlling and leaving different thickness coatings on a continuous web. A jet finishing assembly includes a support means and at least two rotatably mounted jet finishing knives. The orifice opening of each knife is a different height corresponding to a different thickness coating to be left on the web. When the coating thickness requirement for the web changes, the finishing knives are rotated until a knife having the appropriate orifice opening for leaving the required coating thickness is adjacent the passing web.

Abstract: A culvert having a corrosion resistant composite coating and a method of producing the corrosion resistant composite coating. The coating method is for use in a conventional hot dip coating line of the type wherein a steel strip, having been appropriately pretreated so as to be at or above the coating temperature and have its surface free of oxides, is caused to pass through a bath of molten coating metal. A fibrous aramid paper is bonded to the surface of the steel strip by pressing the fibers into the molten coating layer immediately after the steel strip exits the coating bath. The steel strip may be fabricted into construction products such as culvert which may be further protected with bituminous type coatings.

Abstract: An apparatus for uniformly feeding grinding balls to a grinding mill. The apparatus includes a ball storage hopper, a regulator and an inclined chute for conveying balls from the hopper to the regulator. The chute includes a panel for controlling the depth of the balls. The regulator includes a discharge drum having a plurality of compartments adapted to receive the balls, an electric motor for rotating the drum, and a means for retaining the balls in the drum. The drum is rotated at a predetermined speed and feeds the balls into a mill at a uniform rate which can be controlled to approximately match the attrition rate of the balls in the mill.

Abstract: Preloaded connection for supporting an annular body from an annular suspension joint. The connection includes an actuating ring, a split locking ring and a retaining nut which are positioned between the annular body and suspension joint. The connection is preloaded by applying an axial force to the actuating ring causing the locking ring to be expanded outwardly with the annular body becoming preloaded in compression and the suspension joint preloaded in tension with the preload force passing through the mating surfaces.

Abstract: Liquid cooling system for a multiple plate friction clutch. The cooling system provides cooling liquid completely around the contact surfaces of the friction discs and driving members of the clutch at the time the clutch is disengaged or during engagement of the clutch and the driven members of the clutch are stationary or rotating only slowly.

Abstract: There is shown a pressure loaded external gear pump with a low pressure lubrication system. The low pressure lubrication system utilizes the viscous shear pumping effect which occurs between the shafts and bearings to draw fluid from the inlet port, circulate it past the bearings and then return it to the inlet port.

Abstract: A variable pitch diameter torque sensing pulley assembly which includes a first pulley half with a hub and a second pulley half mounted on the hub for axial and rotational movement. The assembly includes two sets of cams and a set of cam followers for biasing the pulley halves toward each other with a force which varies directly as the torque being transmitted by the pulley assembly varies. The two sets of cams are arranged so that one set of cams transmits torque when the pulley halves are close together and biases the pulley halves toward each other with a relatively small axial force based upon the torque being transmitted and the other set of cams transmits torque when the pulley halves are far apart and biases the pulley halves toward each other with a relatively large axial force based upon the torque being transmitted.