High-pressure down-the-hole drill bit (drill)

Summary:

In the high-pressure down-the-hole rock drilling project, to achieve the purpose of high-efficiency and rapid rock drilling, it is necessary to choose high-quality and efficient down-the-hole drill bits, that is, to choose different structures of down-the-hole drills according to different drilling methods and rock types drill. A series of factors such as the end face structure of the bit, the shape of the powder discharge groove, the carbide tooth profile and size, and the hardness of the bit body directly affect the drilling rate, drilling quality, blast hole straightness, bit life and work efficiency. Therefore, it is very important to choose a suitable drill bit in rock drilling engineering.

As far as high-pressure down-the-hole drill bits (drills) are concerned, there are four main types of end face design currently used, namely: convex end face, flat end face, concave end face and deep concave center end face. Cemented carbides mostly use button teeth, spring teeth or button teeth, which are common methods for spring teeth.

1. Convex end face: Convex end face high-pressure down-the-hole drill bits (drill bits) can maintain a high drilling rate when drilling medium-hard and hard abrasive rocks, but the drilling straightness is poor and not applicable Rock drilling projects requiring high blast hole straightness.

2. End face plane type: The end face plane type high wind pressure DTH bit (drill bit) is relatively strong and durable, suitable for drilling hard and extremely hard rocks. At the same time, it is also suitable for drilling medium-hard and soft rocks that do not require high straightness of the blasthole.

3. Concave end face: Concave end face type high wind pressure down-the-hole drill bit (drill bit) has a conical depression on the end surface, which makes the drill bit form a slight nucleation effect during rock drilling, and maintains the drill bit’s centering performance. The chiseled blasthole has good straightness. In addition, this kind of drill bit has a better powder discharge effect and a faster drilling speed. It is a high-pressure down-the-hole drill bit that is currently used in the market.

4. End face deep concave central type: End face deep concave central type high wind pressure DTH drill bit (drill bit) has a deep concave central part at the center of the end face, which is used for nucleation during rock drilling, and deep hole drilling can maintain the blast hole Straightness, but its end face strength is weaker than other types of drill bits, so it is only suitable for drilling soft and medium-hard rocks.