Quantum Leap(QL) Button Bit

The Quantum Leap® line of (DTH ´s) are designed for use on drilling machines in conjunction with a top head or kelly drive mounting. The mounting must be capable of supplying sufficient hold down, hold back, rpm, torque, hammer lubrication, air pressure, and air volume.

DTH ´s achieve high productivity in hard rock applications by adding percussion to the drilling process. Rotary drilling methods use the combination of raw weight and rotation to chip and carve rock from a hole. The rotary method works fine in soft formations where adequate weight and stress can be applied to the rock to initiate fracture and chipping. However, in harder rock the rotary method cannot supply sufficient load on the bit inserts to crack the rock and produce a chip.

Percussion drills overcome the rotary bit load limitation by producing a very high load during impact of the hammer. This load is sufficient to drive the cutting inserts into the rock to produce chips.

Quantum Leap® DTH ´s are recommended for practically any hard rock application. Depending on the size downhole drill being used, they are suitable for drilling water wells, primary blast holes in quarries, open pit mining, coal stripping operations, oil and gas exploration, and construction jobs where large volume rock excavation is required.

Common DTH ´s operate by using the position of a piston to direct supply and exhaust air to and from drive and return volumes. The drive volume "drives" the piston toward impact and the return volume ''returns'' the piston in preparation for another impact stroke. In order to maximize impact energy it is desirable to deliver supply pressure to the drive volume while the piston is at the top of its stroke, and, turn off the supply pressure when the piston is nearly at its impacting position.

However, conventional DTH ´s which use position dependent fixed porting are not able to alter the position at which supply pressure is delivered and shut off from the drive chamber. As a result, maximum efficiency and power are limited.

The Atlas Copco Quantum Leap® DTH cycle overcomes this inherent limitation by using a poppet valve to maximize efficiency. The poppet valve opens and directs supply air to the drive chamber at the top of the piston stroke and cuts off supply air just before impact. Variable drive volume supply timing is the key difference between the Quantum Leap® cycle and common DTH cycles.

DTH drilling tool is widely used in underground mining, quarries, hydraulic and Hydro-Power Engineering, water well drilling, Mineral exploration, anchoring hole drilling, geothermal engineering, Subway excavation, another civil engineering. it has the advantage of high flatness, smooth hole wall, high rigid of drill rod and hammer, independent of high axial thrust, no limit of drilling depth, low cost of devices and easiness to maintain. At the drilling hole of dia.105mm-dia.500mm, a plenty of the DTH drilling tools are used.

Advantage:

1. Button bit is well known for its high wear resistance on medium-hard to hard abrasive rock formations (between 200 Mpa to 260 Mpa compressive strength).Featuring spherical tungsten carbide inserts that is known to have strong configuration against carbide fracture.

2. Recommended for eliminating hole deviation

3. Widely used drifting and tunneling

4. Bit face design is ideal for medium-hard to hard abrasive rock

Products Parameters:

1. high and low air pressure down-the-hole drill bits

2. Low air pressure holeDia.: 65 ~ 220mm

3. High air pressure hole Dia.: 85 ~ 305mm

4. Face type: drop center bit/concave face/convex face/double gauge face/flat face bit

5. Carbide button shape: domed/round button parabolic/semi-ballistic button ballistic button sharp button flat button

6. Drill rock type:  Granite, Marble,  Limestone, Basalt, etc.

7. Project types: Blast holes, Quarry, Anchoring, Infrastructure, Geothermal holes, Well drilling, etc.

Bit face shape selection:

1. Drop Center Bit

For high penetration rates in soft to medium hard and fissured rock formations. Low to medium air pressures. Maximum hole deviation control.

2. Concave Face

The all-round application bit face specifically for medium hard and homogenerous rock formations. Good hole deviation control and good flushing capacity.

3. Flat Face Bit

This kind of face shape is suitable for hard to very hard and abrasive rock formations in applications with high air pressures. Good penetration rates an resistance to steel wash.

4. Double Gauge Face

This kind of face shape is suitable for fast penetration rates in medium to hard rock formations. Designed for high air pressures and good resistance to steel wash step gauge bit.

5. Convex Face

For high penetration rates in soft to medium-hard with low to medium air pressures. It is the most resistance to steel wash, and may reduce the load and wear on the gauge buttons, but poor hole deviation control.