SWD series down-the-hole drill is widely used in cement, metallurgy, mine and quarry mining as well as the blasthole drilling for railway, highway, water conservancy and hydropower and national defense construction projects. The aperture coverage is D90-250. As the most advanced down-the-hole drill rig, it has efficient high pressure down-the-hole drilling system which contributes to high precision, high efficiency drilling and blasting hole. The international procurement, computer optimization design, power matching as well as dvelopment and application regarding load adaptation system realize the overall power matching of power system from the power to the pump and then to the load, which effectively reduces the energy consumption of the machine and ensuring the best performance and high reliability of the machine.