Outside the square hole drill:

With the wind hole impactor supporting the use of benefit back to Java.

Double-wall drill pipe:

Double-wall drill pipe is used for reverse circulation drilling of a drilling tool, drilling, circulating medium flows from the double-wall drill hole bottom annular space, carrying core (sample) return to the ground from the middle of the hole, can effectively prevent the well wall collapse, increase core (sample) take rate, with the factory anti-cycle gas (water) faucet and GQ hollow DTH hammer and can successfully complete the cycle of continuous anti-coring (sample) drilling.