DTH Reverse Circulation Hammers and Bits

Reverse Circulation DTH RC Hammer

RC series reverse circulation DTH Hammer is the latest developed product of our company. It is mainly used for deep exploration drilling and ore grade control.
It has the following characteristics:
1. Based on previous experience of ordinary hammers, combined with the features of recerse circulation hammer, optimized internal structure and ideal energy transfer, thus ensuring the series of hammers deilling with fast smooth and continuous sampling.
2. The internal structure is very simple with components of high rigidity, thus ensuring long life and easy maintenance of the hammer.
3. The collection tube adopts an intergrative design and can be replaced without disassembling the hammer. With carburizing treatment, it has good abrasive resistance.
4. Equipped with bits designed with patent. Simply by replacing the drill bit, the same hammer can drill holes of different sizes ensuring that the sample is not contaminated.
5. In difficult condition such as loose soil, hard rock and plenty of water exists, sampling can be done well.

Working principle
1. With the piston resting on the percussion bit and the hammer closed up in the drilling position, high pressure air is directed into the bottom chamber of the Hammer and the piston lifts. This commences the piston cycle.

2. As the piston travels upwards it forms the top chamber by forming a seal with the inner tube and the ID the piston. Further movement seals the port that feeds the bottom chamber and also simultaneously releases the seal on the bottom chamber allowing the air to expand and exhaust down the splines of the percussion bit. At the same time the Top chamber port is opened which feeds the high pressure air into the previously formed top chamber thus increasing the pressure above the piston and forcing it back down.

3.During the down cycle or power stroke the piston reseals the bottom chamber on the piston bearing bush thus stopping the exhaust air and creating a chamber of high pressure air below the piston which forces the piston back up the hammer.

4. Lifting the hammer of the bottom of the hole allows the percussion bit to slide down the drive sub also allowing the piston to slide down the hammer and rest on the piston bearing bush. The piston strike face and the strike face of the percussion bit can now not come into contact thus allowing the free flow of high pressure air directly through the hammer without the hammer cycling.