Abstract: A method for securing a wellbore string device to a wellbore liner tubular employs a swelling elastomer to frictionally grip a gap between the wellbore string device and the liner tubular. The swelling elastomer is positioned between the wellbore string device and the wellbore liner tubular, then activated to cause it to swell to engage the wellbore string device with the wellbore liner tubular. The wellbore string device may be a centralizer, a wear band or a torque ring.

Abstract: Retrieving a down hole tool at a lower end of a string of casing can be performed with drill pipe during a casing-while-drilling operation. The operator suspends the casing in the well from a drilling rig floor opening. A string drill pipe is lowered into the casing while the casing is suspended for engaging and retrieving the down hole tool. When circulation is desired, the operator secures a circulation tool to an upper end of the drill pipe, then lowers the drill pipe and the circulation tool to close off an upper end of an inner annulus between the drill pipe and the casing. The operator circulates fluid down the circulation tool and the drill pipe and back up an outer annulus surrounding the casing. The connection between the circulation tool and the casing allows the operator to reciprocate the casing.

Abstract: An earth boring bit assembly has a tubular mandrel carried by a casing shoe at the lower end of a string of casing. The casing shoe has stabilizer blades spaced circumferentially apart from each other. A cutter arm seat is formed on the leading edge of each blade at a lower end of the casing shoe. Windows are formed in and spaced circumferentially around the mandrel. A cutter arm is pivotally mounted within each window of the mandrel and movable from an extended position located within one of the cutter arm seats to a recessed position within its window. The cutter arm seats support the cutter arms for torque and axial weight. A sleeve inside the mandrel prevents the cutter arms from pivoting to a recessed position until the sleeve is moved to a released position.

Abstract: A safety valve has a body with a passage extending through it that intersected by a chamber and inclined guide surfaces located in the chamber. A single slab gate with an aperture has ramp surfaces on one side. When moving from the open position to the closed position, the ramp surfaces slide onto the guide surfaces and push the gate into sealing engagement with a side of the chamber to block the passage. The safety valve is particularly useful during a casing-while-drilling operation wherein it is mounted to the upper end of the casing when the casing gripper and top drive are disconnected from the casing string.

Abstract: A pipe gripping assembly having a quill, an actuator and a drive assembly mounts to a top drive of a drilling rig. The quill is connected to a mandrel in the drive assembly. The drive assembly has a tapered mandrel and a set of slips that move along the taper into and out of engagement with the pipe. The actuator is connected to both the quill and a portion of the drive assembly. The actuator includes a motor and at least two sleeves that are threaded together. One sleeve has a spline on its outside diameter that mates to the motor and a gear. Power applied to the motor causes the actuator to move slips in the drive assembly into an engagement position that grips the pipe for lifting and rotating the pipe.

Abstract: A bottom hole assembly in a casing-while-drilling operation is retrieved by displacing the fluid in the casing string with a less dense fluid than the fluid in the annulus. The bottom hole assembly moves upward in the casing string in response to an upward force due to the different densities of fluid in the casing string and in the annulus. Displaced fluid flows out of the casing string and through a restrictive orifice of a choke. The flow area of the orifice is varied as the bottom hole assembly moves upward to control the rate at which the bottom hole assembly moves upward.

Abstract: A bottom hole assembly in a casing-while-drilling operation is retrieved attaching a wireline to the bottom hole assembly. The density of the fluid in the casing string is lightened to a lesser density than the fluid in the annulus, thereby creating a pressure differential between fluid above the bottom hole assembly and fluid below the bottom hole assembly to exert an upward force on the bottom hole assembly. The operator pulls upward on the wireline to assist the upward force in moving the bottom hole assembly up the casing string.

Abstract: During casing-while-drilling, drilling fluid is pumped through a conduit leading to a flow passage a casing string gripper and down the casing string. A bottom hole assembly is mounted at a lower end of the casing string for drilling a wellbore. The bottom hole assembly is retrieved by mounting a circulation sub to the casing string below the casing string gripper, the circulation sub having a lateral outlet. A return flow line is connected from the outlet to the circulation system. The operator flows fluid downward in an annulus of the casing string and back up the casing string, causing the bottom hole assembly to move upward. The fluid flowing back up the casing string is diverted through the outlet in the circulation sub to the circulation system without passing through the flow passage in the casing string gripper.

Abstract: A bottom hole assembly in a casing-while-drilling operation is retrieved by reducing the density of the fluid in the casing string above the bottom hole assembly, creating an upward force on the bottom hole assembly. As the bottom hole assembly moves upward in the casing string, fluid is pumped into the upper end of the annulus and displaced fluid flows out of the upper end of the casing string. The flow rate of the fluid flowing into the upper end of the annulus and the flow rate of the displaced fluid flowing out of the casing string are monitored and compared.

Abstract: A casing-while-drilling bottom hole assembly is releasably connected with a casing string. A retrieval tool is run into the casing string and latched to the bottom hole assembly. Slips are mounted to the retrieval tool, the slips being retracted during running in. Differential pressure moves the retrieval tool and bottom hole assembly upward, and the slips engage the casing string to prevent downward movement if the pressure differential drops too low. A flow passage extends through the retrieval tool and the bottom hole assembly. A check valve in the retrieval tool allows downward flow through the flow passage but prevents upward flow, so that fluid may be circulated through the retrieval tool and bottom hole assembly while suspended with the slips.

Abstract: A bottom hole assembly is retrieved through a casing string by lightening the density of the drilling fluid in the casing string above the bottom hole assembly to a lesser density than the drilling fluid in the casing string annulus. The bottom hole assembly moves upward in the casing string in response to an upward force created by the different densities of fluid. While moving upward, less dense fluid being displaced by the upward movement of the bottom hole assembly flows from the casing string. When the bottom hole assembly stops moving upward, slips suspended it at that intermediate point in the casing string. The operator now lightens the density of the drilling fluid in the casing string below the bottom hole assembly, again creating an upward force on the bottom hole assembly that causes the bottom hole assembly to move upward in the casing string.

Abstract: A slip assembly for gripping pipe during well drilling operations has a housing with a hole for receiving a section of pipe. Pockets in the housing are spaced circumferentially around the hole. Each of the pockets has side walls that face toward each other and are connected to each other by a back wall that has at least one ramp surface. A slip segment is located in each pocket, each slip segment having side edges that engage the side walls of one of the pockets. Each slip segment has a back side with a ramp surface that engages the ramp surface on the back wall of the pocket. Each of the slip segments is movable within its pocket from an upper outward position to a lower inward position in gripping engagement with the pipe.

Abstract: An installation system for installing a liner in a well includes drilling while simultaneously running the liner. A string of drill pipe with a bottom hole assembly including a drill bit on a lower end is lowered into the liner while the liner is suspended at the rig floor. The bottom hole assembly engages a lower sub of the liner for torque transmission. A running tool secured to the drill pipe engages the upper sub such that the running tool supports the weight of the liner and transmits torque. The drill pipe and liner are rotated to drill deeper into the welbore. The liner hanger can be set to engage the casing, then released and reset at a different point.