Bit face shape selection:
1. Drop Center Bit
For high penetration rates in soft to medium hard and fissured rock formations. Low to medium air pressures. Maximum hole deviation control.
2. Concave Face
The all-round application bit face specifically for medium hard and homogenerous rock formations. Good hole deviation control and good flushing capacity.
3. 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.
4. 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.
5. Flat Face Bit
This kind of face shape is suitable for hard to very hard and abrasive rock formations in applications with high air pressures. Good penetration rates an resistance to steel wash.
| DTH hammer type | SRHD55 | SRHD55C | SRHSD5 | SRHQL5 | |
| Length(less bit) mm | 1214 | 1160 | 1175 | 1156 | |
| Weight(less bit) kg | 76.5 | 72.5 | 72.5 | 73 | |
| External diameter mm | Φ125 | Φ125 | Φ125 | Φ125 | |
| Bit shank | COP54 DHD350R | HD55C DHD350Q | SD5 | QL50 | |
| Hole range(mm) | Φ135-155 | Φ135-155 | Φ135-155 | Φ135-155 | |
| Connection thread | API 2 3/8"Reg | API 2 3/8"Reg | API 3 1/2"Reg | API 3 1/2"Reg | |
| API 3 1/2"Reg | API 3 1/2"Reg | ||||
| Working pressure | 1.0-2.5Mpa | 1.0-2.5Mpa | 1.0-2.5Mpa | 1.0-2.5Mpa | |
| Impact rate at 1.5-1.7Mpa | 25Hz | 25Hz | 25Hz | 25Hz | |
| Recommended Rotation speed | 20-35r/min | 20-35r/min | 20-35r/min | 20-35r/min | |
| Air consumption | 1.0Mpa | 9.0m3/min | 9.0m3/min | 9.0m3/min | 9.0m3/min |
| 1.8Mpa | 15.0m3/min | 15.0m3/min | 15.0m3/min | 15.0m3/min | |
| 2.4Mpa | 23.0m3/min | 23.0m3/min | 23.0m3/min | 23.0m3/min | |
PACKAGE
