Abstract: A non-rotating stabilizer tool is provided for connection within a drilling string for stabilization and centralization of the drill string within a well bore being drilled by a rotary drill bit. The tool incorporates an elongate stabilizer and centralizer mandrel having upper and lower collars for its connection within the drill string. The mandrel defines an external circumferential stabilizer receptacle having a cylindrical surface and upper and lower shoulders which are lined with a wear resistant low friction material. The mandrel defines a plurality of axially spaced circumferential seat grooves which interrupt the cylindrical receptacle surface and the friction resistant lining. A stabilizer is rotatably mounted within the stabilizer receptacle by a plurality of wear pads that are seated within the circumferential seat grooves and provide rotatable support for the stabilizer with its inner periphery disposed in spaced relation with the lining of the stabilizer receptacle.

Abstract: For use in a drilling string including drill collars, a safety joint which enables the string of drill pipe to be unthreaded from the drill collars at the safety joint is disclosed. A safety joint utilizes a collet telescoped within and threaded to an outer tubular member connected in the drill string. They are held together by a releasable lock pin which is inserted and retracted to thereby enable the drill string to be separated at the safety joint so that remedial steps can be taken to free the remainder of the drill string. The safety joint is also capable of being actuated mechanically under control from the surface.Particular valve and signal receivers are disclosed herein including frequency responsive structural components which vibrate on being inflicted with a particular ultrasonic signal. The vibratory components oscillate and thereby initiate leakage of hydraulic oil from a pin locking system. Several alternate forms are disclosed.

Abstract: An improved broach is disclosed incorporating, in the preferred and illustrated embodiment, an elongate tubular member constructed in the fashion of a drill collar having a raised external thread cut thereon in helical fashion, the thread having a top face. The thread tapers from the bottom to a maximum diameter at a very gradual rate. The top face includes a generally flat, exposed surface which is reinforced with particulate tungsten carbide. It additionally includes inserts of tungsten carbide at periodic locations as, for example, inserts located at ninety-degree intervals along the thread face. The inserts extend relatively deep and are constructed of a solid block of tungsten carbide in a supportive alloy. Another form has inserts made of cylindrical pellets.

Abstract: For use in a drilling string, the preferred and illustrated embodiment depicts a drill collar to be placed in the lower parts of the drill string for straightening the hole. The preferred embodiment utilizes a generally square drill collar with a thick or heavy wall. It is square in cross section along the greater portion of its length, the four corners being slightly rounded to a specified diameter on rotation, and the four lengthwise corners of the regular cross section are all reinforced with hardfacing material to a specified depth, typically tungsten carbide. The four edges abrade the bore hole as the drill string penetrates the earth. In addition, the lower end of the tubular body includes lengthwise flutes in the form known on a stabilizer to guide the hole straightening device into the hole to be reamed by operation of the device.