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 Type	Abrasiveness	Rock Hardness	Item No.
Clay,Shale,Siltstone,Gypsum	Medium	Soft	ZZ1
Ash Stone,Coal,Argillite, Volcanics,Sandly Pebble	Very High	Soft	ZZ1/ZZ2
Sandstone,Sandy Shale,Lithoid Limestone,Limonite Sandstone	Very High	Medium Soft	ZZ2
Medium-hard Limestone,Medium-hard Shale,Medium-hard Ash Stone	High	Medium	ZZ3/ZZ4
Marble,Hard Schist,Hard Streak Stone	Medium	Medium	ZZ5/ZZ6
Diabase,Andesite,Gneiss	Medium	Medium Hard	ZZ6/ZZ7
Grandiorite,Limonite	Medium	Medium Hard	ZZ7/ZZ8
Granite,Basalt,Hard Streak Stone	Medium to Low	Hard	ZZ8/ZZ9
Crystauize Genesis,Rhyolite, Quartz Porphyry	Medium to Low	Hard	ZZ9/ZZ10
Silicious Stone,Hard Sandstone	Medium to Low	Extreme Hard	ZZ11/ZZ12
Rhyolite Porphyry,Dense Quartzite,Iron Stone	Low	Ultra Hard	ZZ14

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 Hardness	Diamond Grit Size	Recommended Shape	Diamond Grade
Soft to Medium	10/15	Step Type	A
Medium to Hard	20/25	Step/Semi-round Type	A
Medium Hard to Hard	30/40	Step/Semi-round Type	AA
Hard	40/60	Semi-round Type	AA
Hard to Very Hard	60/80	Round Type	AAA

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.

Type	PDC Bits Size Available
PDC Core Bits	N,H,P,N2,N3,H3,P3, T2 101,T6 86,T6 101,T6 116,T6 146,412,HWF,PWF.
PDC Noncoring Bits	28mm,32mm,42mm,48mm,56mm,65mm,76mm, 85mm, 96mm,99mm,115mm,123mm,143mm,152mm.

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.

Type	PDC Bits Size Available
Rod Shoes	A,B,N,H,P,HWT,BTW,NTW,NT,HT,PT.
Casing Shoes	AW,BW,NW,HW,PW,SW,PWT, 66mm,76mm,86mm,101mm,116mm,131mm,146mm.

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.

Type	PDC Bits Size Available
Backpack Drill Bits	26mm,31mm,36mm,42mm,46mm,48mm, 51mm,56mm,57mm,59mm,64mm,74mm

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.

Type	PDC Bits Size Available
Chip Core Bits	A,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 Bits	A,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.