Start with the cutting structure

Milled-tooth and tungsten-carbide-insert tricone bits use different cutting structures. Milled teeth are generally discussed for softer formations where tooth geometry and cleaning are important. TCI designs are commonly considered as formation strength and abrasive wear demands increase. The final choice still depends on the specific design, bearing, gauge protection and operating window.

Describe the formation beyond one rock name

• Strength and compressive behavior
• Abrasiveness and hard inclusions
• Fracture, bedding and interbedded intervals
• Sticky cuttings or balling tendency
• Water and circulation conditions

Confirm the complete bit requirement

Send the diameter, connection, required circulation route, available weight on bit, rotary speed range and rig information. Bearing and seal options must be reviewed with the expected operating environment and project target.

Compare wear, not only penetration

Uneven cone wear, tooth loss, gauge wear, bearing condition and erosion provide clues for the next discussion. Photographs should show the complete bit and each cone. Add operating records and formation intervals so the wear can be interpreted in context.

Final order confirmation

Confirm cutting structure, bearing, diameter, connection, nozzle or circulation arrangement, marking and quantity on the released specification. Do not substitute a visually similar tricone without checking these interfaces.