Drill Bits

 Impregnated Synthetic Diamond Core Bits

The impregnated diamond core bit has emerged as the most commonly used type in the mineral exploration industry. CDG’s impregnated Diamond Core Bit performance is the product of many years of research, coordinating diamond grading and selection technology, bit design, matrix composition and manufacturing processes with extensive testing under a very wide range of drilling conditions. The result- China Drilling impregnated core bit can be designed and produced to give the best performance and economic results under any specified drilling conditions.

Rock TypeAbrasivenessRock HardnessItem No.
Ash Stone,Coal,Argillite,
Volcanics,Sandly Pebble
Very HighSoftZZ1/ZZ2
Sandstone,Sandy Shale,Lithoid Limestone,Limonite SandstoneVery HighMedium SoftZZ2
Medium-hard Limestone,Medium-hard Shale,Medium-hard Ash StoneHighMediumZZ3/ZZ4
Marble,Hard Schist,Hard Streak StoneMediumMediumZZ5/ZZ6
Diabase,Andesite,GneissMediumMedium HardZZ6/ZZ7
Grandiorite,LimoniteMediumMedium HardZZ7/ZZ8
Granite,Basalt,Hard Streak StoneMedium to LowHardZZ8/ZZ9
Crystauize Genesis,Rhyolite,
Quartz Porphyry
Medium to LowHardZZ9/ZZ10
Silicious Stone,Hard SandstoneMedium to LowExtreme HardZZ11/ZZ12
Rhyolite Porphyry,Dense Quartzite,Iron StoneLowUltra HardZZ14

 Surface-set Diamond Bits

The surface-set diamond bit differs from the impregnated diamond type in that they are set with a single layer of natural drill diamond on the working surfaces of the bit crown in a pre-determined pattern. The diamonds are mounted in a bit crown powdered metal matrix body that is fused to a steel tool body or shank.

Rock HardnessDiamond Grit SizeRecommended ShapeDiamond Grade
Soft to Medium10/15Step TypeA
Medium to Hard20/25Step/Semi-round TypeA
Medium Hard to Hard30/40Step/Semi-round TypeAA
Hard40/60Semi-round TypeAA
Hard to Very Hard60/80Round TypeAAA

 PDC Bits

The PDC bits, include the core and non-coring types, have been used in soft to medium formation of hardness 3-6.

The surface of the disc-shaped cutting element consists of very fine synthetic diamond powders sintered together by a high pressure, high temperature process. Backing this diamond layer is a tungsten carbide stud which is brazed directly into the bit matrix by a special process. These cutters can take the enormous compressive and shear loads generated during drilling without failure or erosion.

PDC core bits are ideal for use on high powered drills at relatively low rotation speeds. Remarkable results have been obtained both in bit life and penetration compared with surface set bits.

TypePDC Bits Size Available
PDC Core BitsN,H,P,N2,N3,H3,P3,
T2 101,T6 86,T6 101,T6 116,T6 146,412,HWF,PWF.
PDC Noncoring Bits28mm,32mm,42mm,48mm,56mm,65mm,76mm, 85mm,

 Rod Shoes & Casing Shoes

The surface-set diamond casing shoes and rod shoes are recommended for soft to medium hard formations while impregnated casing shoes and rod shoes are recommended for hard and fractured formations.

The rod shoe is made into semi-round type crown profile. The casing casing shoe is made into “V” crown surface.

The impregnated casing shoes and rod shoes can be made into different hardness matrix and different matrix height as customer’s request.

TypePDC Bits Size Available
Casing ShoesAW,BW,NW,HW,PW,SW,PWT,

 Backpack Drill Bits

Backpack drill bits has been used for handheld drill which has been found to be best used as a near-surface initial scanning and mapping tool.

TypePDC Bits Size Available
Backpack Drill Bits26mm,31mm,36mm,42mm,46mm,48mm,

 Tungsten Carbide Core Bits

The tungsten carbide bit uses tungsten carbide as the cutting media. This kind of bit has a perfect cost performance when drilling softer unconsolidated formations that are mainly composed of clay,sand,gypsum or soft shale.

TypePDC Bits Size Available
Chip Core BitsA,B,N,N2,H3,H,H3,P,P3,NW,HW,PW,SW,HWT,NT,HT,PT,
T2 76,T2 86,T2 101,T6 116,T6 146.
Insert Tungsten Carbide Core BitsA,B,N,N2,H3,H,H3,P,P3,NW,HW,PW,SW,HWT,NT.HT,PT,
T2 76,T2 86,T2 101,T6 116,T6 146.