Rock drilling tools are generally composed of rock drill bits, drill rods, coupling sleeves, and shank adapters, and rock drill bits are the parts that bear the most impact and wear in the entire system. Rock drill bit needs to be connected to drill rod and driven by the rock drill to break the rock mass. Its service life is short because direct drill into rock mass. To prolong the service life of the rock drill bit, the drill rod-cone matched with the drill bit should use a professionally manufactured high-quality tapered drill rod as much as possible. In addition, pay attention to the correct connection of the rock drill bit.

1. The taper, surface roughness, and diameter of the small end of the drill rod must be checked and qualified.

2. The taper hole of the drill bit should be sprayed with soft metals such as zinc-aluminum alloy or equipped with a qualified red copper liner.

3. The depth of the cone into the cone hole should be carried out as required.

These methods have been accepted by many countries. In Japan, chisel bits and cross bits connected by the cones are all covered with copper linings. And Sweden Secoroc drill bit’s tapered hole always be sprayed zinc coating. Zinc spraying on the taper hole can also prevent corrosion of the skirt body by acidic mineral water.

The correct connection of the drill bit is very important for the constructors. A rock drill bit should connect to the drill rod before drilling, although we cannot directly observe how the rock drill bit breaks the rock in the drilling. However, the approximate process of drilling can be inferred from known conditions such as drilling progress, rock drill thrust, rock softness, drill bit failure, and stripped rock particles. If the rock drill bit is not correctly connected before drilling, not only may the presumed result be deviated but also the result of low construction efficiency and short service life.