BD DRILL produce the broadest range of hammers, bits, and related equipment. This means more choices for you. It means you can work with the strongest support network in the industry, regardless of your
equipment needs. It means that you can look to one reliable and time tested source for all your equipment needs.
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The optimum range of hole size for blast hole drilling with DTH is 90 mm to 254 mm (3 ?"–10″). Smaller blast holes are generally drilled using top hammer, and larger holes generally use rotary machines.
In other applications, like foundation drilling, DTH hammers can be used with 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.
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.
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What is the down the hole (DTH) hammer:
Down the hole hammers are rock drilling equipment which takes compressed air as power source to partially transfer impact power into drilling holes. An air distributing device in a top hammer controls a piston to move back and forth. An impact device arranged in the front of the top hammer transfers the impact powderto a down-the-hole bit to crush rocks.
1. Based on previous experience of ordinary hammers, combined with the features of reverse circulation hammer, optimized internal structure and ideal energy transfer, thus ensuring the series of hammers drilling 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 integrative 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 conditions such as loose soil, hard rock and plenty of water exists, sampling can be done well.
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How to use the Down The Hole (DTH) Hammer function?
When percussion or hammer drilling the percussion mechanism is called a DTH or down the hole
hammer. This drilling tool is located directly above the down hole hammer bit. The driller transfers
weight to the bit through the drill pipe as well as provides some rotation. Through the use of a compressor, the pressurized air is forced to the down hole hammer. As the drilled hole gets deeper the driller adds more drill pipe to the string. The piston strikes the impact zone of the hammer bit; hammers are always used as part of a casing advancement system and can be used in reverse circulation applications. DTH hammers are common when drilling blast holes and water wells.
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Suitable choice of raw material, advanced processing technology and perfect quality warranty.
With hardened treatment, drilling life can be extended and then cost can be reduced.
Size range 3’’, 3.5’’, 4’’, 5’’, 6’’, 8’’, 10’’, 12’’ etc.
Shank styles: DHD3.5, DHD340, DHD350, DHD360, DHD380; COP44, COP54, COP64, COP84;
TD40, QL50, QL60, QL80; Mission40, Mission50, Mission60, Mission80; SD4, SD5, SD6, SD8.
- Valveless air distribution. More reliable.
- Simple design of the piston. Long life.
- More efficient energy transfer, fact drilling speed, lower air consumption and lower oil consumption.
- Fewer internal parts, simple structure, long life, less failure and easier to maintain because all the parts are heat treated.
- Easy to disassemble because the top sub, the drive chuck and the external cylinder are connected by multi-step thread.
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