The essence of DTH rock drilling is to make the impactor dive into the hole during rock drilling to reduce the energy loss caused by the impact energy transmitted by the drill rod, thereby reducing the effect of hole depth on rock drilling efficiency. Down-the-hole rock drilling equipment is a down-the-hole drilling rig. YQ-80, YQ-100 and QZ-165 are commonly used in China's underground mines.
Down-the-hole drilling rig is an impact rotary drilling rig. Its internal structure is different from that of a general rock drill. Its gas distribution and piston reciprocating mechanism are independent, that is, an impactor. The front end is directly connected to the drill bit and the rear end is connected to the drill rod. When rock drilling, the impactor dives into the hole, and through the gas distribution device (valve), the piston (hammer) in the impactor reciprocates against the drill tail, so that the drill bit impacts the rock at the bottom of the hole. The high-speed rotation of the impactor in the hole is achieved by a separate turning mechanism, that is, a motor or a wind-driven rotating device outside the hole, through a drill rod connected at the rear end of the impactor. Rock dust generated during rock drilling is flushed out of the hole by a mixture of wind and water. The mixed gas is injected into the impactor by the powder discharge mechanism through the center of the drill pipe, and then enters the bottom of the hole through the air groove on the impactor cylinder.
When opening the hole, start the motor first, and when the transfer is normal, move the manipulator's push handle. Give it a proper propulsive force, and then pull the handle that controls the impactor to the working position. After rock drilling, the water valve can be opened to keep the gas-water mixture in a proper ratio. Perform normal rock drilling. When advancing work moves the drill rod into contact with the holder, a drill rod is drilled for drilling. To stop the motor and stop supplying air and water to the impactor, insert the fork into the drill pipe slot of the bracket, make the motor reverse the slide and back, disconnect the joint from the drill pipe, and then connect the second drill pipe. Now you work continuously in a loop.