Field Case Study: φ94 Three-Wing Concave Stepped-Wing Bit

650 m per bit in limestone (f=8) drilling conditions

1.Working Conditions

2.Formation & Drilling Parameters

3.Performance After Field Use

• • After 650 m of accumulated drilling, the bit body remained structurally intact and the stepped-wing profile stayed clearly recognizable.
  • The PDC cutters remained firmly bonded, with high cutter retention and no abnormal chipping or detachment observed.
  • Wear on the main cutting area and gauge area was concentrated in the normal contact zones, showing controlled and even wear.
  • In limestone and alternating hard-soft roadway conditions, the bit delivered stable guidance, low deviation tendency, and strong impact and wear resistance.
  • Well suited for medium-hard rock, interbedded formations, and general underground drilling such as water detection, gas drainage, and grouting holes.

4.Image Comparison

New bit	Bit after field use

5.Key Advantages

• • High footage performance: Achieved 650 m per bit in limestone (f=8), helping reduce bit changes and improve drilling continuity.
  • Stable guidance: The concave profile combined with stepped wings helps improve hole stability and reduce deviation.
  • Reliable cutter bonding: Firmly bonded PDC cutters provide strong impact resistance and reduce the risk of cutter loss.
  • Long wear life: Even wear distribution supports reliable service life in medium-hard and abrasive formations.
  • Broad applicability: Suitable for water detection, gas drainage, grouting, and other underground drilling applications.

6. Summary

Summary: This φ94 three-wing concave stepped-wing bit achieved 650 m per bit in limestone (f=8) conditions, combining stable guidance, wear and impact resistance, and reliable cutter bonding—an efficient solution for medium-hard rock and complex roadway drilling.