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Technical Specifications


8 1/2 FS3

Diameter: 215.9mm (8 1/2")  
IADC Code: 137  
Design number: UT275  
State standard designation: МС-ЦГАУ  


Gradient angle of axle journal 33°
Axle journal offset relative to drill bit axis 4.80 mm
Bearing type Journal bearing
Sealing Elastomer
Total number of inserts (inner/heel row) 85 (42/43)
Total number of insert rows (inner/heel row) 8 (5/3)
Number of changeable nozzles 4
Connecting thread З-117 (4 1/2 REG)
Drill bit net weight, kg 34.40
Drill bit gross weight, kg 35.90

Recommended Drilling Conditions

Rotation speed 180-40 rpm
Thrust load 7.00-18.00 t (15400 - 39600 lbs)
The lower level of rotation speed value corresponds the upper level of thrust load value and vice versa.


The drill bit is designed for drilling soft formations with medium hard streaks

Design Features


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