Abstract: A non-weldable workpiece may be affixed to a weldable workpiece by friction stirring the weldable workpiece to plasticize and extrude at least a portion thereof into a recess in the non-weldable workpiece. The weldable workpiece may then be welded to a body of a downhole tool to enable the welding of a non-weldable workpiece onto a body to increase the wear-resistance of the body.

Abstract: A non-weldable workpiece may be affixed to a weldable workpiece by friction stirring the weldable workpiece to plasticize and extrude at least a portion thereof into a recess in the non-weldable workpiece. The weldable workpiece may then be welded to a body of a downhole tool to enable the welding of a non-weldable workpiece onto a body to increase the wear-resistance of the body.

Abstract: Methods and apparatuses for hydraulically fracturing a subterranean wellbore while drilling and/or tripping are disclosed. A method for hydraulically fracturing a subterranean formation may include rotating a drill string to drill the wellbore and hydraulically fracturing the subterranean formation at a plurality of axially spaced locations along the wellbore while tripping the drill string out of the wellbore. The drill string may include a hydraulic fracturing assembly. The hydraulic fracturing operation may include translating the drill string in an uphole direction so that a set of frac ports in the hydraulic fracturing assembly is adjacent a region of the formation selected for fracturing, expanding at least one pair of packers to seal an annular region of the wellbore exterior to the frac ports, and pumping fracturing fluid downhole through the frac ports to hydraulically fracture the subterranean formation.

Abstract: A drill bit assembly for measuring reservoir formation properties comprises a bit head and a pin body, and an electrically insulated gap joint between two conductive parts of the drill bit assembly. The electrically insulating gap joint can fill a gap between bit head and pin body engagement sections such that the bit head and pin body are mechanically connected together at connecting ends but electrically separated. Alternatively or additionally, the pin body can have two pieces which are separated by an electrically insulating gap joint. An electrical conductor is electrically connected at a first end to the bit head and is communicable at a second end with an alternating current signal to transmit an alternating current into the bit head, thereby inducing an electric current into a reservoir formation adjacent the bit head.