Home / Products / Tricone / Extremely Hard 8xx / 9″ MR845
9″ MR845 Tricone Bit
IADC 845 · Φ229mm · 50kg · 4 1/2″ API
Cutting structure & formations
Gage rows: Conical. Inner rows: Conical. For hard formations with high compressive strength.
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″ / Φ229 mm, weight 50 kg
- Connection 4 1/2″ API, bearing Roller-Ball-Roller-Thrust Button/Sealed Bearing
- WOB 45,000–72,000 lbs, rotary speed 50–80 rpm
Technical parameters
| Model | MR845 |
|---|---|
| IADC code | 845 |
| Diameter | 9″ / Φ229mm |
| Thread | 4 1/2″ API |
| Weight | 50 kg |
| Bearing type | Roller-Ball-Roller-Thrust Button/Sealed Bearing |
| Circulation | Jet Air |
| Inner row teeth | Ovoid |
| Gage row teeth | Ovoid |
| Gage bevel protection | Round |
Operating suggestions
Actual parameters must be set per application
| Weight on bit | 45,000–72,000 lbs |
|---|---|
| Rotary speed | 50–80 rpm |
| Air back pressure | 0.2–0.4 MPa |
| Formation strength | 58,000–70,000 Psi |
