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9 7/8″ MR845 Tricone Bit
IADC 845 · Φ251mm · 65kg · 6 5/8″ API
Cutting structure & formations
Gage rows: Ovoid. Inner rows: Ovoid. For extremely hard formations with high compressive strength, typically magnetite quartzite, quartzite, granite.
ORIGINAL · EN Ovoid on gage, ovoid on inner rows. Designed for extremely hard and abrasive formations with high compressive strengths such as magnetite quartzite, quartzite, granite.
Shirttail protection
Hardmetal and wear resistant carbide on shirttail lip and lug.
ORIGINAL · EN Hardmetal and wear resistant carbide on shirttail lip and lug.
- Diameter 9 7/8″ / Φ251 mm, weight 65 kg
- Connection 6 5/8″ API, bearing Roller-Ball-Roller-Thrust Button/Sealed Bearing
- WOB 49,375–79,000 lbs, rotary speed 50–80 rpm
Technical parameters
| Model | MR845 |
|---|---|
| IADC code | 845 |
| Diameter | 9 7/8″ / Φ251mm |
| Thread | 6 5/8″ API |
| Weight | 65 kg |
| Bearing type | Roller-Ball-Roller-Thrust Button/Sealed Bearing |
| Circulation | Jet Air |
| Inner row teeth | Ovoid |
| Gage row teeth | Ovoid |
| Gage bevel protection | Flat-top |
Operating suggestions
Actual parameters must be set per application
| Weight on bit | 49,375–79,000 lbs |
|---|---|
| Rotary speed | 50–80 rpm |
| Air back pressure | 0.2–0.4 MPa |
| Formation strength | 58,000–70,000 Psi |
