Unlike other rock drilling tools, the impactor remains at the bottom of the hole during the drilling process, and the impactor directly impacts the drill bit to break the rock. The compressed gas enters the impactor through the drill pipe and is discharged from the drill bit, and the exhaust gas is used for slag removal. The rotary motion of the impactor is provided by the rotary head and the shaft thrust is provided by the thruster, which is transferred to the impactor through the drill pipe.
The piston, inner cylinder, air distribution seat, check valve and drill attachment are installed in the outer cylinder, and the upper end of the outer cylinder is equipped with the upper joint with wrench square and coupling thread, and the lower end is equipped with the snap ring sleeve with coupling thread. The snap ring controls the axial movement of the drill bit. The backstop valve is used to prevent rock slag and other debris from entering the impactor when the supply of pressurized air is stopped. During the drilling process, the drill bit is pushed into the impactor and pressed against the snap ring sleeve, at which time the piston directly impacts the drill bit for rock drilling. When the drill bit is lifted off the bottom of the hole, the impactor starts to blow the rock slag at the bottom of the hole.
|Product Name||DTH Hammer Drilling Tool|
|Machine Type||Drilling Tool|
|Range|| DHD340 Hammer @10bar Air Consumption 5M³/min|
DHD340 Hammer @18bar Air Consumption 10.2M³/min
DHD340 Hammer @24bar Air Consumption 15M³/min
DHD350 Hammer @10bar Air Consumption 7.5M³/min
DHD350 Hammer @18bar Air Consumption 14.7M³/min
DHD350 Hammer @24bar Air Consumption 19.5M³/min
The optimum range of hole size for blast hole drilling with DTH is 90 mm to 254 mm (3 ½”-10″). Smaller blast holes are generally drilled using a top hammer, and larger holes generally use rotary machines.
In other applications, like foundation drilling, DTH hammers can be used with a single bit in hole sizes up to. 750 mm (30″). With multiple hammer units CD (Cluster drills) drill holes up to 70″ or 1778 mm.
As a rule of thumb, the smallest hole diameter a DTH hammer can drill is its nominal size. A 4-inch hammer will drill a 4-inch (102 mm) hole. The limiting factor is the outside diameter of the hammer, because, as the hole diameter reduces, airflow is restricted. The maximum hole size for production drilling is the nominal hammer size plus 1 inch, so for a 4-inch hammer, the maximum hole size is 5 inches (127-130 mm).
Choosing the right hammer is largely determined by 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 cuttings to evacuate the hole.
Drilling Dia. Range: holes from 90mm to 800mm
Application Fields: Widely used in open pit and underground mining,Water well drilling.,Deep well,Foundaion,Anchor drilling