Home / Products / Tricone / Hard Formation 7xx / 12 1/4″ MR742
12 1/4″ MR742 Tricone Bit
IADC 742 · Φ311mm · 98kg · 6 5/8″ API
Cutting structure & formations
Gage rows: Conical. Inner rows: Conical. For hard formations with high compressive strength.
ORIGINAL · EN Ovoid on gage, ogive and ovoid on inner rows. Designed for hard and abrasive formations with high compressive strengths such as granite, limestone, sandy sandstone, dolomite and chert.
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 12 1/4″ / Φ311 mm, weight 98 kg
- Connection 6 5/8″ API, bearing Roller-Ball-Roller-Thrust Button/Open Bearing
- WOB 49,000–85,750 lbs, rotary speed 60–90 rpm
Technical parameters
| Model | MR742 |
|---|---|
| IADC code | 742 |
| Diameter | 12 1/4″ / Φ311mm |
| Thread | 6 5/8″ API |
| Weight | 98 kg |
| Bearing type | Roller-Ball-Roller-Thrust Button/Open Bearing |
| Circulation | Jet Air |
| Inner row teeth | Ogive and ovoid |
| Gage row teeth | Ovoid |
| Gage bevel protection | Round |
Operating suggestions
Actual parameters must be set per application
| Weight on bit | 49,000–85,750 lbs |
|---|---|
| Rotary speed | 60–90 rpm |
| Air back pressure | 0.2–0.4 MPa |
| Formation strength | 46,000–56,000 Psi |
