New Arrival China Electric Water Well Drilling Rig - Down the hole dth sd mission 6” hammer and bit price – TDS

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 tophammer, 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.

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 hole diameter reduces, airflow is restricted. 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 inch (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.

Model	Thread Connection	OD(mm)	Rec.Hole Size	Shank Style	Working Pressure(Bar)
CD35	API 2 3/8″ Reg	φ82mm	φ90-φ105	DHD3.5 CD35	1.0-1.5Mpa
CD45	API 2 3/8″ Reg	φ99mm	φ110-φ135	Cop44 DHD340 CD45	1.0-2.5Mpa
CSD4	API 2 3/8″ Reg	φ99mm	φ110-φ135	SD4 CSD4	1.0-2.5Mpa
CQL40	API 2 3/8″ Reg	φ99mm	φ110-φ135	QL40 CQL40	1.0-2.5Mpa
CD55	API 2 3/8″ Reg API 3 1/2″ Reg	φ125mm	φ135-φ155	Cop54 DHD350R CD55	1.0-2.5Mpa
CSD5	API 3 1/2″ Reg	φ125mm	φ135-φ155	SD5 CSD5	1.0-2.5Mpa
CQL50	API 3 1/2″ Reg	φ125mm	φ135-φ155	Cop54 QL50 CQL50	1.0-2.5Mpa
CD65	API 3 1/2″ Reg	φ148mm	φ155-φ190	Cop64 DHD360 CD65	1.0-2.5Mpa
CSD6	API 3 1/2″ Reg	φ148mm	φ155-φ190	SD6 CSD6	1.0-2.5Mpa
CQL60	API 3 1/2″ Reg	φ148mm	φ155-φ190	Cop64 QL60 CQL60	1.0-2.5Mpa
CD85	API 4 1/2″ Reg	φ185mm	φ195-φ254	Cop84 DHD380 CD85	1.0-2.5Mpa
CSD85	API 4 1/2″ Reg	φ185mm	φ195-φ254	SD8 CSD8	1.0-2.5Mpa
CQL80	API 4 1/2″ Reg	φ185mm	φ195-φ254	QL80 CQL80	1.0-2.5Mpa
CSD10	API 4 1/2″ Reg API 5 1/2″ Reg API 6 5/8″ Reg	φ225mm	φ254-φ311	SD10 CSD10	1.0-2.5Mpa
CN100	API 6 5/8″ Reg	φ225mm	φ254-φ311	NUMA100 CN100	1.0-2.5Mpa
CSD12	API 6 5/8″ Reg	φ275mm	φ305-φ445	SD12 CSD12	1.0-2.5Mpa