28 3/4 - 32 in QDG7419(730.25 - 812.8 mm)

ER 20460 IADC S243

Design Specifications

Total Cutters100
Cutter Size16mm (5/8 in), 19mm (3/4 in)
Face Cutters(8) 16mm, (92) 19mm
Gauge Cutters(8) 16mm, (92) 19mm
Drill Out Cutters(8) 16mm, (92) 19mm
Conditioning Cutters(8) 16mm, (92) 19mm
Blade Count7
Pilot Diameter22"
Maximum Tool Diameter24 1/4 in
Nozzles6 Reamer Series 60N
Junk Slot Area (sq in)400.86
Gauge Length3"
Gauge ProtectionOptions Available
Upper Connection7-5/8" API Reg.
Lower Connection7-5/8" API Reg. Box
LengthMake-Up: 69 3/4 in Overall: 69 3/4 in
Fishing NeckDiameter: 9 1/2 in Length: 22 7/8 in

Operating Parameters

Rotary SpeedSuitable for Rotary & PDM
Weight-on-Bit8,000 To 40,000 (lbs)
3,636 To 18,180 (daN)
4 To 18 (Tonnes)
Flow Rate (GPM)800 To 1500
Hydraulic Horsepower (HSI)1 To 6
The operating parameters listed here are general parameters, please contact your local Schlumberger representative for precise recommendations for your individual well.


Pilot conditioning section improves tool stability & by stress relieving the formation with this intermediate stage, drilling the larger hole can be done at a more aggressive ROP

Drill collar connections allow flexible drillstring placement to optimize reamer and BHA performance.

Both the pilot hole section and the reamer cutting structure contain PDC inserts & carbide hardfacing on gauge to maintain hole integrity and extend tool life.

Short gauge length improves directional responsiveness without compromising hole integrity or tool stability.