Basical Parameter | |
Bit Size | 8 3/4"(222.2MM) |
IADC Code | 127 |
Tooth Type | Steel /Milled Tooth |
Bearing Type | Elastomer Sealed Bearing |
Connection | 4 1/2"API reg pin |
Rotary Speed(rpm) | 180~80 |
Weight on Bit(KN/MM) | 0.35~1.00 |
Formation | low compressive strength,high drill-ability and soft formation,like shale,clay,salt rock and soft limestone,etc. |
8 3/4 inch is a regular size in water well drilling, it is working well with small capacity drilling rigs and widely used in the world.
Steel tooth tricone rock bit is also named milled tooth tricone rock bit could drill soft mudstone, even soft limestone, the cones are hard faced by tungsten carbide, the bearing is journal and locked by ball, high grade elastomer(rubber)-HNBR O-ring sealed bearing, grease compensating system lubricate the bearing , the working life is very long.
Application
Well Drilling Water Well Drilling
IADC | Rock formation | WOB (KN/mm) | WOB (KN/mm) |
116/117 | Low compressive strength, high drill-ability and extremely soft formation, like soft shale, clay, conglomerate etc. | 0.35~0.90 | 180~80 |
126/127 | Low compressive strength, high drill-ability and soft formation, like shale, clay, soft limestone, salt rock, etc. | 0.35~1.00 | 180~80 |
136/137 | Soft to medium soft with low compressive strength or soft with hard interlayer, like anhydrite, soft limestone,sandstone, etc. | 0.37~1.05 | 130~60 |
216/217 | Medium hard formation with relatively high compressive strength and hard interlayer, like hard shale, sandstone, limestone, etc. | 0.5~1.20 | 100~50 |
