Abstract: Methods of removing casing from a wellbore, the method including disposing a drilling tool assembly in a wellbore, the drilling tool assembly including a cutting device, a spearing device, and a jarring device. The methods further including activating the cutting device, cutting a first casing segment, deactivating the cutting device and activating a spearing device. The method further including engaging the spearing device with the first casing segment, activating the jarring device to free the first casing segment, and removing the first casing segment from the wellbore.

Abstract: A mechanical set anchor wherein a plunger extending from a base end of an anchor body activates a pin type trigger which releases a spring utilized to set multiple slips extending from the body of the anchor. Continued downward compressive forces fully sets the slips into the borehole pipe casing. The slips are maintained in their fully set position by a locking nut. The slips are further set into the pipe casing after slips are released from the anchor body. The anchor is mechanically released by an upward pull under tension of sufficient strength to shear release pins that release the compressed spring fully retracting the slips within the anchor body so that the anchor may be tripped from the borehole without interference from the previously engaged slips.

Abstract: A mechanical set anchor wherein a plunger extending from a base end of an anchor body activates a pin type trigger which releases a spring utilized to set multiple slips extending from the body of the anchor. Continued downward compressive forces fully sets the slips into the borehole pipe casing. The slips are maintained in their fully set position by a locking nut. The anchor is mechanically released by an upward pull under tension of sufficient strength to shear release pins that release the compressed spring fully retracting the slips within the anchor body so that the anchor may be tripped from the borehole without interference from the previously engaged slips.

Abstract: A two trip sidetrack casing milling apparatus for elongating and enlarging a previously formed window in a cased borehole in preparation for a subsequent sidetracking drilling operation is disclosed. The apparatus consists of three mills on a shaft, a first window mill is secured to an end of a shaft. The first window mill forms a diameter larger than a diameter of a subsequent sidetracking drill bit that is passed through the window. A second pilot mill is secured to the shaft and strategically positioned above the first window mill. The second pilot mill forms a diameter that is less than the diameter of the first window mill. A third watermelon mill is secured to the shaft and strategically positioned above the second pilot mill. The third watermelon mill forms a diameter that is at least the same diameter as the first window mill.

Abstract: A starter mill adapted for use with a whipstock to mill a window through the casing of a well for deviating the direction of drilling. The starter mill includes a bearing nose which is utilized to indicate completion of the milling process. As the mill nears completion of the milling process, the bearing nose will become wedged between the whipstock face and the casing preventing further downhole movement. The bearing nose will engage whipstock and casing, allowing the work string to continue to rotate although the decreased torque resulting from the absence of milling provides a clear signal that the milling operation is complete. The cutters of the mill are spaced a predetermined distance from the bearing nose to ensure completion of the casing window.

Abstract: A wellhead severing system for detonating a liquid explosive charge and subsequent removal of the wellhead from the sea floor. The explosive severing system includes a charge container holding a liquid explosive and a contractable bladder in fluid communication with the charge container to compensate for pressure and temperature variations as the system is lowered to the wellhead in the sea floor. Liquid explosive from the bladder flows into the charge container maintaining a constant volume of uncontaminated explosive around the detonators. The severing system is lowered into the wellhead on a running string and detonated through high voltage wires extending to a connector or the surface.

Abstract: A detonation assembly for an explosive wellhead severing system which employs a battery pack lowerable through a drill string to engage and power the detonation assembly positioned within the well bore. The lowerable unit includes a biased shutter which seals the contacts from discharge of the battery pack by the surrounding fluids. The shuttered unit is lowered into contact with the receiving unit to arm the detonation assembly. Until the power unit is lowered into engagement, the severing system is not armed. In case of malfunction or misfire, the power unit can be retrieved to disarm the detonator assembly. The entire assembly is housed within the drill string to isolate the critical elements from the surrounding environment.