A drill string rotation controller includes an anti-torque balance module, a TC bearing retaining ring, an upper TC bearing, an upper thrust ball bearing, an upper Haval ring, a middle seal retaining ring, an upper mandrel, an upper shell, a rotary control cylinder, an upper spring, a spline shell, a spline sleeve, a spline mandrel, a lower shell, a spring push sleeve, a lower spring, a floating piston, a lower mandrel, a bulkhead, a lower thrust ball bearing, a lower Haval ring, a lower TC bearing, a conversion joint, an anti-drop joint, a lower joint, and a control pin. The rotary control cylinder causes the spline sleeve to switch the transmission relationship between the spline mandrel and shell. Therefore, the drill string rotation controller controls the conversion between the composite drilling mode and the directional drilling mode.

A down the hole drilling assembly having an elongate casing, a fluid powered piston, top and bottom working chambers, a plurality of fluid passages and an exhaust system, wherein the sum of the top work area and a top intermediate work area of the piston is equal to the cross-sectional area of the casing bore.

A down the hole drilling assembly having an elongate casing, a fluid powered piston, top and bottom working chambers, a plurality of fluid passages and an exhaust system, wherein the sum of the top work area and a top intermediate work area of the piston is equal to the cross-sectional area of the casing bore.

The present disclosure relates to a rock drill bit for a percussive drilling hammer positioned at the cutting end of a hammer. The drill bit includes a head, an elongated shank connected to the head at a front end of the bit, a head-shank transition area where the head connects to the shank, an anvil at the rear end of the shank for receiving the impact of the piston, a plurality of buttons provided at the front face of the head configured to engage the material to be crushed in the intended direction of drilling, and a plurality of flushing passages extending through the head and having at least one opening at the front face of the head. An angle formed between the head and the shank at the head-shank transition area is greater than 100 degrees.

The present disclosure relates to a rock drill bit for a percussive drilling hammer positioned at the cutting end of a hammer. The drill bit includes a head, an elongated shank connected to the head at a front end of the bit, a head-shank transition area where the head connects to the shank, an anvil at the rear end of the shank for receiving the impact of the piston, a plurality of buttons provided at the front face of the head configured to engage the material to be crushed in the intended direction of drilling, and a plurality of flushing passages extending through the head and having at least one opening at the front face of the head. An angle formed between the head and the shank at the head-shank transition area is greater than 100 degrees.

A ground drilling device with a percussion piston for drilling into the soil, comprising at least one housing section for the percussion piston, wherein an insert is arranged in the housing between the drilling head tip and the percussion piston such that the insert transmits at least a portion of the energy of the percussion piston to the housing, and the insert is held in the housing by means of a shrinking adhesion connection.

A drilling rig and methods are provided for using multiple types of drilling when installing geothermal systems. The drilling rig can perform sonic drilling such as percussive sonic drilling and a type of non-sonic drilling. Control switching valves are added to the hydraulics of the drilling rig to selectively provide sufficient flow of hydraulic fluid to motors used in the multiple types of drilling, depending on which type of drilling is currently most efficient for the underground formation being drilled. The water pump and hydraulic motor for such have been designed to handle both types of drilling on a small drilling rig frame, thereby allowing for the drilling to occur in space-constrained environments. A method of recycling water used to remove cuttings during drilling to put back downhole is also provided.

A drill bit assembly for fluid-operated percussion drill tools. The assembly comprises a percussion bit comprising a bit head detachably connected to an axially extending shank and engagement means formed on an external wall of the shank engageable with complementary engagement means formed internally of a drive chuck whereby rotational drive from the chuck may be transmitted to the shank. At least one flushing channel extends between the external wall of the bit shank and a cutting face of the bit head, to provide a fluid path for a flushing medium between the external wall of the bit shank and the cutting face of the bit head.

A drill bit assembly for fluid-operated percussion drill tools. The assembly comprises a percussion bit comprising a bit head detachably connected to an axially extending shank and engagement means formed on an external wall of the shank engageable with complementary engagement means formed internally of a drive chuck whereby rotational drive from the chuck may be transmitted to the shank. At least one flushing channel extends between the external wall of the bit shank and a cutting face of the bit head, to provide a fluid path for a flushing medium between the external wall of the bit shank and the cutting face of the bit head.

A coating architecture is disclosed that includes a substrate having a surface finish R.sub.a of 0.3μ or finer, an intermediate layer overlying and in contact with the substrate; and a solid lubricant layer overlying and in contact with the intermediate layer. The test results of applying the coating architecture to a reciprocating hammer drill utilizing the coating is also disclosed.