A polycrystalline diamond drill bit for percussion drilling, in small hole high silica ground is disclosed which has a cutting face having an inner flat face and an outer beveled peripheral surface, a number of first polycrystalline diamond tipped inserts having a first diameter inserted into the inner flat face and the outer beveled peripheral surface, and a number of second polycrystalline diamond tipped inserts having a second diameter inserted into the inner flat face, with the second diameter being different than the first diameter. The cutting angle and the radius of the tip of each insert in addition to the diameter of the inserts, provide for use of a machine thrust pressure and machine torque pressure at low ranges when the PCD bits are used in percussion drilling. The percussion drilling, with larger bits, may be used for rotary oil drilling, and operating at a machine thrust and torque of less than 20 Bar.

Application of polyaminated fatty acid-based oil compositions to additive particles to control dusting. A method reducing an amount of dust produced during transfer of additive particles in well operations may comprise providing treated additive particles comprising additive particles and a polyaminated fatty acid-based oil composition disposed on a surface of at least portion of the particles, wherein the polyaminated fatty acid-based oil composition comprises a polyaminated fatty acid and an organic solvent. The method may further comprise mixing components comprising the treated additive particles and a base fluid to provide a treatment fluid. The method may further comprise introducing the treatment fluid into a subterranean formation.

A downhole apparatus connected to a workstring within a wellbore. The workstring is connected to a bit member. The apparatus includes a mandrel operatively connected to a downhole motor mechanism, an anvil member operatively formed on the bit member, the anvil member being operatively connected to the mandrel, a radial bearing housing unit operatively connected to the workstring, with the radial bearing housing unit being disposed about the mandrel, and a hammer member slidably attached to the radial bearing housing unit.

The present invention relates to a method for optimising energy usage at a drilling arrangement. The method includes the step of determining an acceleration of a drilling head in the drilling arrangement. The method further includes determining a parameter related to the energy usage at the drilling arrangement based on the determined acceleration. The method even further includes optimising the energy usage based on the determined parameter. The present invention also relates to a system for optimising energy usage at a drilling arrangement, to a computer program, and to a computer program product.

A drilling assembly for percussive drilling includes at least two of a drill bit, a drill rod and a guide adapter. A peripheral surface of the shoulder on the drill rod is at least partially encased in both radial and axial directions inside the mounting sleeve of the drill bit or the mounting sleeve of the guide adapter, and/or the peripheral surface of the shoulder on the guide adapter is at least partially encased in both radial and axial directions inside the mounting sleeve of the drill bit.

A drilling assembly for percussive drilling includes at least two of a drill bit, a drill rod and a guide adapter. A peripheral surface of the shoulder on the drill rod is at least partially encased in both radial and axial directions inside the mounting sleeve of the drill bit or the mounting sleeve of the guide adapter, and/or the peripheral surface of the shoulder on the guide adapter is at least partially encased in both radial and axial directions inside the mounting sleeve of the drill bit.

Disclosed is a hammer reamer comprising cutting wheels, a product-pulling feature, and a hammer component operable to deliver a percussive cycle of an internal piston component. Notably, an internal impact surface within the head of the hammer reamer is positioned relative to the piston component in the hammer consistent with a sweet spot position of a drill bit used in a pilot boring configuration. Unlike a slidably engaged drill bit, however, the internal impact surface in the hammer reamer is fixed in place so that the impact surface remains in the sweet spot of the piston stroke range. In this way, even though the hammer reamer is being pulled back through a bore while the drill string is being retracted, the hammer component may continue to deliver percussive blows to the hammer reamer head to introduce a vibratory force that contributes to the efficiency of the reaming process.

A threaded connection for tubing having a pin connection with external, tapered buttress type threads, preferably with a one inch per foot thread taper, the pin threaded portion having seven threads per inch. The connection also includes a box connection having complementary internal threads threadedly engaging the pin, the box connection having a comparable pitch and thread taper.

A threaded connection for tubing having a pin connection with external, tapered buttress type threads, preferably with a one inch per foot thread taper, the pin threaded portion having seven threads per inch. The connection also includes a box connection having complementary internal threads threadedly engaging the pin, the box connection having a comparable pitch and thread taper.

An electrical submersible pump assembly has a motor with a stator stack of limitations. The stack has slots through which magnet wires are wound. An encapsulate surrounds and bonds the magnet wires together within each slot. The encapsulate includes ceramic particles within a polymer adhesive matrix. The polymer matrix may be a fluoropolymer adhesive. Each of the magnet wires may have an electrical insulation layer surrounding a copper core. The ceramic particles are rounded and much smaller than a cross-sectional area of each of the magnet wires. At least some of the magnet wires may be in contact with a perimeter of the slot. The ceramic particles may be porous.