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■ Bit Face Shape Selection
Drop Center For high penetration rates in soft to medium hard and fissured rock formations. Low to medium air pressures. Maximum hole deviation control.
Concave Face The all-round application bit face special for medium hard and homo-generous rock formations. Good hole deviation control and good flushing capacity.
Convex Face For high penetration rates in soft to medium-hard with low to medium air pressures. It is the most resistance to steel wash, and may reduce the load and wear on the gauge buttons, but poor hole deviation control.
Flat Face This kind of face shape is suitable for very hard and abrasive rock formations in applications with high air pressures. Good penetration rates an resistance to steel wash.
Double Gauge Face This kind of face shape is suitable for fast penetration rates in medium to hard rock formations. Designed for high air pressures and good resistance to steel wash step gauge bit.
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