Abstract: A stabilizer design for improving the likelihood of recovery of a drill string when obstructions are encountered in a wellbore is disclosed herein. The stabilizer includes a tubular body, a track, and a stabilizer blade. The track is disposed along the tubular body. The stabilizer blade is operatively coupled to the track and is configured to slide along the track from a first position to a second position.

Abstract: A stabilizer design for improving the likelihood of recovery of a drill string when obstructions are encountered in a wellbore is disclosed herein. The stabilizer includes a tubular body, a track, and a stabilizer blade. The track is disposed along the tubular body. The stabilizer blade is operatively coupled to the track and is configured to slide along the track from a first position to a second position.

Abstract: A modified casing coupling houses a pressure relief valve body having a through bore with opposing end openings. The through bore communicates with the interior of the modified casing coupling at one end opening thereof and with an area surrounding the modified casing coupling at an opposite end opening. The through bore includes a ball seat adjacent one end opening thereof which receives a sealing ball. The ball is urged in the direction of the ball seat by a tensioning element. The ball is exposed to annular pressure trapped between successive lengths of well casing located in the well borehole. The amount of tension exerted on the ball by the tensioning element is selected to allow the ball to move off the ball seat to release trapped annular pressure between the selected casing strings once a certain annulus pressure is reached.

Abstract: A modified casing coupling houses a pressure relief valve body having a through bore with opposing end openings. The through bore communicates with the interior of the modified casing coupling at one end opening thereof and with an area surrounding the modified casing coupling at an opposite end opening. The through bore includes a ball seat adjacent one end opening thereof which receives a sealing ball. The ball is urged in the direction of the ball seat by a tensioning element. The ball is exposed to annular pressure trapped between successive lengths of well casing located in the well borehole. The amount of tension exerted on the ball by the tensioning element is selected to allow the ball to move off the ball seat to release trapped annular pressure between the selected casing strings once a certain annulus pressure is reached.

Abstract: A non-upset tubing section, a tubular coupling, a connection for non-upset tubing sections, and a method for connecting the non-upset tubing section and the tubular coupling are disclosed. Methods for fabricating the non-upset tubing section and the tubular coupling are also disclosed. In one embodiment, the non-upset tubing section has an outer diameter of about 23/8 inches and, in another embodiment has an outer diameter of about 27/8 inches. The non-upset tubing section also has an externally tapered threaded surface having approximately eight rounded threads per linear inch. The tubular coupling has an outer diameter of about 27/8 inches, for use with at least one 23/8 inches OD tubing section, or about 31/2 inches, for use with at least one 27/8 inches OD tubing section. The coupling also has an internally tapered threaded surface having approximately eight rounded threads per linear inch and having a pitch diameter of about 2.258 inches for use with the 23/8 inches OD tubing section or about 2.

Abstract: Threaded pipe sections are connected to form a tubular joint having proper sealing positioning at proper make-up torque. This improved connection includes a first pipe section having a registry mark of a prescribed width at a predetermined position on its exterior surface for the proper axial engagement of the pin member with the coupling or box member. This position is principally determined from finite element analysis. This position is the same for all pin members of a similar size, grade, weight and thread form and therefore can be applied with a template. The pin member and box member are continuously threaded together up to a minimum of an empirically predetermined torque range. This torque range is predetermined by a combination of finite element analysis and experimentation of representative joints for a certain type, size, weight and grade of pipe section. If required, the range is adjusted by empirically determined friction factors to account for different platings, surface treatment and lubricants.

Abstract: An apparatus for detecting substantially longitudinal flaws in the end area of a tubular member is disclosed. The apparatus comprises magnetizing-detection units, means for moving-said units along a helical path about the surface of the end area of the tubular member, and means for centralizing and securing the apparatus on the end of the tubular member being inspected. Magnetic detection transducers on the magnetizing-detection units detect perturbations in the applied magnetic field in the area of any substantially longitudinal flaws. The magnetic detection transducers are mounted so as to remain remote from the surface of the tubular member during operation of the apparatus. The field is generated in the tubular member by said magnetizing-detection units. The magnetizing-detection units are pivotably mounted to allow for movement over both flat and tapered surfaces. The signals generated by the magnetic detection transducers are transmitted to an external indicating device through slip rings.

Abstract: A device for detecting defects in the bore of a tubular member. The device includes an inspection head including an electromagnet for magnetizing the internal surface of a tubular member. The device also includes a sensor or sensors to detect magnetic flux leakage indicative of a defect. The magnetic flux sensor output is sent to a control-data acquisition system concurrently with signals as to the axial and circumferential position of the defect, which are obtained by their respective encoders. The control-data acquisition system is capable of processing and displaying the data in analog and digital form.

Abstract: Apparatus for detecting flaws in the wall of a ferromagnetic pipe is disclosed. The apparatus comprises an electromagnetic having poles in slideable contact with the surface of the wall of the ferromagnetic pipe to form a closed magnetic circuit and means for electrically connecting the coil of the electromagnetic to an input source of alternating current whereby a fluctuating magnetic field is induced generally axially through the wall of the pipe between the poles of the electromagnetic. The apparatus also comprises means adjacent the surface of the wall of the pipe between the poles of the electromagnet for sensing a leakage of the axial magnetic field therefrom and generating a signal corresponding to a sensed portion of the leakage. The apparatus further comprises means for electrically connecting the sensing means to a readable output device.

Abstract: Apparatus for detecting flaws in the threaded end of a ferromagnetic pipe is disclosed. The apparatus comprises means for applying a magnetic force to produce a field generally axially through the threaded end of the pipe, first and second means adjacent successive crests of a thread for sensing a generally radial magnetic field and generating a first and second signal corresponding to the sensed magnetic fields, and means for differentially connecting the signals generated by said first and second sensing means, whereby a differential output signal is produced in response to a flaw between the crests of the thread being inspected. The apparatus also comprises means for helically rotating said sensing means to follow a path corresponding to the threads of the pipe, whereby the first and second signals vary with time.A method for detecting flaws in the threaded end of a ferromagnetic pipe is also disclosed.

Abstract: Two adjacent riser pipes having substantially a common axis are connected by the riser connector of this invention in the manner described below.A connector box, adapted to be attached to the end of one of the pipes, has an abutment surface and adjacent to it a channel transverse to the common axis of the pipes. A locking dog fits slidably in the channel, and has a tapered surface facing the abutment surface of the box and at an angle less than 45.degree. to the direction of the channel. A connector pin, adapted to be attached to the end of the other pipe, has a flange. When the flange is in contact with the abutment surface of the box and when the locking dog is pushed towards the flange by a force applying means, the flange of the pin is held between the tapered surface of the dog and the abutment surface of the box, and the connections between the box, pin, and dog are preloaded by forces greater in magnitude than the force applied by the force applying means.

Abstract: A threaded connection with improved fatigue-life useful for connecting adjacent sections of a pipe string subject to bending, tensile, and compressive stresses such as a drill collar string is disclosed. The connection comprises a pin member which is threadedly engageable with a corresponding box member. In the preferred embodiment, the inventive connection is designed to have bending strength ratio ("BSR") of about 3.20 or greater, and more preferably, in a range between about 3.20 and about 4.00. The preferred thread form of the connection is a V-type thread form having two flank angles of 30 degrees and a 0.038 inch root radius. Other design features may be used in combination with the threaded connection to further improve the connection's fatigue-life.