Dth Hammer

General Introduction:

Superdrill DTH hammers are all simple structure, easy to assemble and disassemble, as well as reliable quality and long service life. Acedrills has various hammer models suitable to drill holes from 64mm to 1000 mm (2-1/2” ~ 39-3/8”) in diameter; and come with three kind: low pressure (5 ~ 7 bars), middle pressure (7 ~ 15 bar) and high pressure ­­(7~ 30 bars).

Superdrill DTH hammers mainly be produced with shank type of DHD, QL, SF, COP, Mission, SD, BR, CIR and ACD series, Diameter ranging from 2” to 8” for mining and quarrying, and 6” to 32” for water-well drilling, oil-well drilling and foundation and so on.

DTH Hammer Selection:

Choosing the right hammer is largely determined by drill machines (mainly compressor output), drilling hole size and type of rock formation. Ideally, the size of the hammer should match the required hole dimension as closely as possible, leaving just enough space for compressed air to flush cuttings and clean the hole.

The optimum range of hole size for blast-hole drilling with DTH method is 90~254 mm (3-1/2” ~ 10”) with 3.5 ~ 8” hammers. Smaller blast holes are generally drilled with top-hammer tools, while larger holes typically with rotary drilling tools. In other applications, like foundation drilling, DTH hammers can be used in hole size up to 1,000 mm (39-3/8”).

Usually, the smallest hole diameter a DTH hammer can drill is its nominal size, for example, a 4” hammer would drill a 4” (100/102 mm) hole. The limiting factor is the outside diameter of the hammer, because, as hole diameter reduces, airflow is restricted. Maximum hole size for production drilling is the nominal hammer size plus 1”for 5” and smaller hammers and plus 2 for 6” and bigger hammers, for example, for a 4” hammer the maximum hole size is 5” (127/130mm) while for a 8” hammer the maximum hole size is 10” (254mm).