Apparatus and methodologies for recovering equipment from a subterranean wellbore are provided, the apparatus operative to both disconnect uphole equipment from downhole equipment that has become lodged in the wellbore, salvaging the uphole equipment, and then to reconnect with the downhole equipment to fish the equipment from the wellbore. More specifically, the apparatus and methodologies comprise a modified fishing tool having two tubular portions that can be easily and efficiently be disconnected and reconnected with one another.

A downhole component including a first portion; a second portion; a controlled failure structure between the first portion and second portion. A method for improving efficiency in downhole components.

A downhole component including a first portion; a second portion; a controlled failure structure between the first portion and second portion. A method for improving efficiency in downhole components.

A pressure pulse system includes a stator, a rotor rotatably positioned in the stator, and a valve assembly configured to induce a pressure pulse in response to rotation of the rotor within the stator, wherein the valve assembly includes a first valve plate coupled to one of the stator and the rotor and including a flow passage, and a second valve plate coupled to the other of the stator or the rotor to which the first valve plate is not coupled and comprising a first flow passage and a second flow passage that is spaced from the first flow passage, wherein the valve assembly provides a first flowpath and a second flowpath between the flow passage of the first valve plate and the second flow passage of the second valve plate.

A drilling assembly comprises a drill bit and a cutting assembly. The drilling assembly forms a longitudinal center axis. The drill bit and cutting assembly fastened to a rotatable spline drive assembly. The cutting assembly being resiliently displaceable to the drill bit along the center axis such that in a first position the drill bit is surrounded by the cutting assembly and in a second position a free end portion of the drill bit projects beyond the cutting assembly along the center axis. The cutting assembly comprises an endmill which comprises a central through hole which is complementary to the outer diameter of the drill bit. A method for cutting swarfs created by drilling with the endmill is described.

An agitator for vibrating a drill string includes an agitator housing, a rotor and an agitation mass. The drill string has a central axis. The rotor is coupled to the agitator housing and being rotatable about an agitator axis. The agitation mass is coupled to the rotor and is rotatable about the agitator axis. During rotation, a center of mass of the agitation mass is spaced apart from the agitator axis to cause deflection of the agitator axis relative to the central axis to produce vibration in the drill string.

A system includes an upper connection having a ring shape with an external surface, where upper splines are formed on the external surface and the upper connection is fixed to the upper section. The system also includes a lower connection having a ring shape with an internal surface, where lower splines are formed on the internal surface and the lower splines are configured to mate with the upper splines of the upper connection. Further, the system includes a fishing sub having a first lateral end and a second lateral end, where the first lateral end is fixed to the lower connection by shear pins configured to shear when a pre-determined tension is applied to the system, and the second lateral end is fixed to the lower section. The upper connection is inserted into the lower connection to form an engagement between the upper section and the lower section.

A system includes an upper connection having a ring shape with an external surface, where upper splines are formed on the external surface and the upper connection is fixed to the upper section. The system also includes a lower connection having a ring shape with an internal surface, where lower splines are formed on the internal surface and the lower splines are configured to mate with the upper splines of the upper connection. Further, the system includes a fishing sub having a first lateral end and a second lateral end, where the first lateral end is fixed to the lower connection by shear pins configured to shear when a pre-determined tension is applied to the system, and the second lateral end is fixed to the lower section. The upper connection is inserted into the lower connection to form an engagement between the upper section and the lower section.

The disclosure presents processes and methods for determining an overpull force for a stuck drill string in a borehole system. The fluid composition of a mud in the borehole at a specified depth can be broken down into a percentage of liquid and percentage of solids, as well as adjusting for material sag and settling factors. The fluid composition can be utilized to identify friction factors and drag in respective fluid composition zones. Each friction factor and drag can be summed to determine a total fluid drag on the drill string. In some aspects, the total fluid drag can be adjusted utilizing the relative positioning of casing collars and tool joints. The total fluid drag can be summed with the other force factors, such as a shear force and mechanical drag. The total drag can then be utilized as the overpull force applied to the stuck drill string.

The disclosure presents processes and methods for determining an overpull force for a stuck drill string in a borehole system. The fluid composition of a mud in the borehole at a specified depth can be broken down into a percentage of liquid and percentage of solids, as well as adjusting for material sag and settling factors. The fluid composition can be utilized to identify friction factors and drag in respective fluid composition zones. Each friction factor and drag can be summed to determine a total fluid drag on the drill string. In some aspects, the total fluid drag can be adjusted utilizing the relative positioning of casing collars and tool joints. The total fluid drag can be summed with the other force factors, such as a shear force and mechanical drag. The total drag can then be utilized as the overpull force applied to the stuck drill string.