DTH (Down The Hole) hammer
The “Down-the-hole” or DTH hammer is used for drilling holes through a wide range of rock types. In DTH drilling, the hammer is located directly behind the drill bit. The drill pipes transmit the necessary feed force and rotation to hammer and bit plus compressed air for the hammer and flushing of cuttings. The drill pipes are added to the drill string successively behind the hammer as the hole gets deeper. The piston strikes the impact surface of the bit directly, while the hammer casing gives straight and stable guidance of the drill bit. This means that the impact energy does not have to pass through any joints at all. The impact energy therefore remains constant, regardless of the hole depth.

- DTH (Down The Hole) hammer range:
3” DTH (Down The Hole) hammer: DHD 3.5, COP 34, COP 32, Mission 30, BR 3, Mach 303;
4” DTH (Down The Hole) hammer: DHD 340/COP 44, COP 42, QL 40, SD 4, Mission 40, XL 4, Mach 44;
5” DTH (Down The Hole) hammer: DHD 350/COP 54, COP 52, QL 50, SD 5, Mission 50, XL 5;
6” DTH (Down The Hole) hammer: DHD 360/ COP 64, COP 62, QL 60, SD 6, Mission 60, XL 6;
8” DTH (Down The Hole) hammer: DHD380, QL 80, SD 8, Mission 80;