Abstract: A method and apparatus for changing the speed of a drill bit down hole in a fluid-actuated motor, including a positive displacement motor and a hydraulic motor, is disclosed. The apparatus comprises a bypass valve installed in the motor for controlling flow through and around the power section of the motor. When closed, the bypass valve forces all fluid to flow through the power section of the motor, imparting maximum speed to the drill bit. When opened, a portion of the fluid flow is allowed to flow around the power section of the motor, thereby reducing the speed of the drill bit. The bypass valve may be opened or closed mechanically, electrically, hydraulically, pneumatically, or by any other means, including a removable plug.

Abstract: A method and apparatus for transporting and assembling a drilling rig is disclosed. The drilling rig of a preferred embodiment of the present invention utilizes specialized positioning pads integral to the side boxes of the drilling rig to facilitate the connection of the center drill floor of the drilling rig to the side boxes of the rig. A preferred embodiment of the present invention may also utilize a specialized positioning dolly and an adjustable fifth-wheel truck connection for transporting the mast to the drill site, assembling the mast sections together, and positioning the mast for connection to the drill floor of the rig. The result is a unique drilling rig design and sequence for assembly that significantly reduces the time required to transport the rig from location to location and to assemble the rig at the drill site.

Abstract: A method and apparatus for connecting sections of a drilling rig substructure is disclosed. The disclosed invention is a unique structural connector in which sections of a drilling rig substructure can be connected together without the use of pins or pin-type connectors. The structural connector of the present invention utilizes specially-shaped fixed members connected to, and extending through, support plates that are attached to sections of a drilling rig substructure that mate with specially-shaped mating lugs that are mounted on mating lug plates that are attached to separate sections of the drilling rig substructure. When the sections of the drilling rig substructure to be connected are positioned together, the specially-shaped mating lugs engage the specially-shaped fixed members and form a high strength structural connection between the sections of the drilling rig substructure.