In high-pressure down-the-hole drilling projects, in order to achieve the goal of efficient and fast drilling, it is necessary to select high-quality and efficient down-the-hole drill bits, that is, to select down-the-hole drill bits with different structures according to different drilling methods and rock types. A series of factors such as the drill bit end face structure, the shape of the powder discharge groove, the carbide tooth shape and size, the hardness of the drill bit body, etc. directly affect the rock drilling rate, drilling quality, blasthole straightness, drill bit life and work efficiency. Therefore, choosing a suitable drill bit is very important in rock drilling projects.
As far as high-pressure down-the-hole drill bits (drill bits) are concerned, there are four main end face design forms currently used, namely: end face convex type, end face flatness, end face concave type and end face deep concave center type. Carbide mostly uses ball teeth, spring teeth or ball teeth and spring teeth for tooth arrangement.
1. Convex end face type: The convex end face type high-pressure down-the-hole drill bit (drill bit) can maintain a high rock drilling rate when drilling medium-hard and hard abrasive rocks, but the drilling straightness is poor, and it is not suitable for rock drilling projects with high requirements for blasthole straightness.
2. Flat end face type: The flat end face type high-pressure down-the-hole drill bit (drill bit) is relatively strong and durable, and is suitable for drilling hard and extremely hard rocks. It is also suitable for drilling medium-hard rock and soft rock with low requirements for blasthole straightness.
3. Concave end face type: The concave end face type high-pressure down-the-hole drill bit (drill bit) has a conical concave part on the end face, which makes the drill bit form a slight nucleation effect during the rock drilling process, maintains the drill bit’s centering performance, and the drilled blasthole has good straightness. In addition, this drill bit has a better dust removal effect and a faster drilling speed. It is a high-pressure down-the-hole drill bit that is currently used more on the market.
4. End face deep concave center type: The end face deep concave center type high wind pressure down-the-hole drill bit (drill bit) has a deep concave center part in the center of the end face, which is used for nucleation in the rock drilling process. Drilling deep holes can maintain the straightness of the blasthole, but its end face strength is weaker than other types of drill bits, so it is only suitable for drilling soft rock and medium-hard rock.
Post time: Aug-15-2024
