Spear Shale-Optimized Steel-Body PDC Bit | SLB


Shale-optimized steel-body PDC drill bit

Drillers checking PDC bit nozzles on rig floor

Reengineered to advance ROP and cuttings evacuation

The Spear bit features a bullet shape and smaller-diameter steel body—proven to reduce bit balling and cuttings packing around matrix-body bit blades—and set the benchmark for drilling curve and lateral sections in unconventional shale plays: 10,000 runs since 2011.

Building on this performance, we used the IDEAS integrated dynamic design and analysis platform to engineer the next-generation Spear shale-optimized steel-body PDC drill bit, which delivers improved ROP while maintaining precise directional control.

This significant increase in drilling performance is the result of several key design enhancements:

  • Taller blades, resulting in an increased junk-slot area, promote cuttings migration from the bit face.
  • Shale evacuation channel around nozzle ports directs cuttings evacuation to inhibit nozzle plugging.
  • Reduced bit body profile improves cuttings evacuation into the annulus.
Spear Shale-Optimized Steel-Body PDC Bit
Spear Shale-Optimized Steel-Body PDC Bit

Advanced fluid modeling

Unconventional shale applications often produce a poor hydraulic environment: high mud weights, low flow rates, and with a bit hydraulic horsepower (HSI) of less than 0.5. In such conditions, bit nozzle placement is crucial.

An extensive computational fluid dynamics (CFD) analysis was conducted to ensure nozzle placement on the next-generation Spear bit resulted in an improved hydraulic configuration: Cutters are more effectively cleaned and cooled, helping to prolong cutter life and maximize ROP. The Spear bit can be fitted with optional Enduro 360 PDC cutters. This new range of premium cutters has greater thermal stability, impact resistance, and durability.

Improved ROP with excellent directional control

When compared with the first-generation PDCs, the next-generation Spear bits have improved ROP in curve and lateral sections 40% while providing excellent directional control for accurate wellbore placement.