DTH drilling is a drilling rig that uses impact method to hammer rock drilling. It is a special rock drilling equipment for drilling the intersection hole of the total wire rope. It adopts the hollow drill pipe of the ball tooth drill. There are many diameters of ball-tooth drill bits, usually used in marble mines with a maximum diameter of no more than 100mm. However, when drilling with seven rounds of guiding wire ropes in the drill hole, it is necessary to drill large holes with a diameter of more than 250mm. When drilling a common intersection hole in a granite mine, the diameter of the hole is generally not more than 110mm, but when drilling a hole with a cutting wheel that guides the beading rope in the hole, the diameter of the hole also needs to exceed 250mm. Good for large drill holes up to 300mm. According to the different shapes of the ball tooth impact surface, the ball tooth bit is divided into a plane ball tooth bit, a concave ball tooth bit and a convex ball tooth bit. According to the different working pressure of the impactor, the ball-tooth drill is divided into low-pressure and high-pressure air supply. DTH drilling rigs are divided into marble mine drilling, granite mine drilling and three different models that can be used in marble and granite mines. The down-the-hole drilling rig usually used in marble mines uses a spherical tooth drill bit with a diameter of 76mm, a drill pipe diameter of 62mm, and a single drill pipe length of 1m. The drilling speed of ordinary marble is 10-12 meters per hour. The down-the-hole drilling rig used in granite mines uses a 90mm diameter ball-tooth drill bit, a drill pipe diameter of 75mm, and a single drill pipe length of 1m. The drilling speed of ordinary granite is 8-10 meters per hour.
