8 1/2 in MDSiR516(215.9 mm)

Product ID: 66728A0001 ER 26880

Design Specifications

Total Cutters46
Rolling Cutter Count9
Cutter Size16mm (5/8 in)
Face Cutters(19) 16mm
Gauge Cutters(5) 16mm
Cone Cutters(6) 16mm
Back-Up Cutters(16) 16mm
Blade Count5
Nozzles5 Standard Series 50N
Bit Connection4 1/2 Reg
Junk Slot Area, in215.104
GaugeLength: 2" Protection: Options Available
LengthMake-Up: 9.829 Overall: 14.017
Fishing NeckDiameter: 6.0 Length: 4.113

Operating Parameters

Bit SpeedDesigned for use on steerable motor
Weight-on-Bit18 To 32 (lbs)
8 To 15 (daN)
To (Tonnes)
Flow Rate galUs/min500 To 600
Hydraulic Horsepower, HSI1 To 6
Recommended Make-up Torque16,600 To 21,600 ft/lbs pound ft
The operating parameters listed here are general parameters, please contact your local Smith Bits representative for precise recommendations for your individual well.



The ONYX 360 rolling cutter feature allows the PDC element to rotate enabling the full circumference of the diamond edge to be utilized. This prevents a wear flat developing in only one place thereby maintaining cutter sharpness for improved drillbit durability.

50-series nozzles offer maximum adjustable total flow area (TFA) for smaller or heavier-set drillbit designs. The nozzles are designed for high efficiency cleaning, cooling, and cuttings evacuation without compromising the cutting structure, which could reduce ROP or bit life.

Strategic placement of cutters on the upside of each blade, to allow backreaming in tight spots, reduces the potential of “bit sticking” while pulling out of the hole. Allows a degree of backreaming, sufficient to condition a borehole without major risk of gauge pad wear

Bit design and performance have been certified through the validation process prescribed by IDEAS simulation technology.

The PX feature places thermally stable diamond inserts (TSP) on the gauge to maximize gauge retention and extend bit life.