Your SlideShare is downloading. ×
11 B   Pdc Bits
Upcoming SlideShare
Loading in...5

Thanks for flagging this SlideShare!

Oops! An error has occurred.

Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

11 B Pdc Bits


Published on

  • Thank you for sharing it with us. It's quite helpful.
    Are you sure you want to  Yes  No
    Your message goes here
  • I would like to have this presentation as power point slide, to make it easy for junior engineers to understand.
    thanks and regards
    Are you sure you want to  Yes  No
    Your message goes here
No Downloads
Total Views
On Slideshare
From Embeds
Number of Embeds
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

No notes for slide


  • 1. Fixed Cutter Bits Early Diamond Bit History • Prior to 1940 natural diamonds were “peened” into a steel head to create a diamond bit. • Due to the high cost and marginal manufacturing technique, diamond drill bit were rarely used. • The primary diamond application was in core bits.
  • 2. Milestones • 1947 - Christensen Develops matrix bit technology for practical attachment of natural diamonds to a drill or core bit head. • 1954 - GE is the first to synthesize diamond. • 1975 - First practical application of man-made diamond with introduction of GE’s “Stratapax” polycrystalline diamond compact (PDC) stud cutter. • 1981 - Introduction of thermally stable polycrystalline (TSP) cutters. PDC Design Presentation • Cutter Technology • PDC Bit Design • Profiles and Blades • Cutter Orientations • Hydraulics • Bit Gauge • Bit Mechanics • Design Optimization
  • 3. Natural Diamond Cutters • Original diamond cutting element. • Monocrystalline diamond. • Different size and quality diamonds for different applications. • Size range expressed as stones per carat (SPC). Natural Diamond Cutters • Natural diamonds are furnaced into the bit head. • Versatile application range when synthetic diamonds are not applicable. • Medium to very hard formations. • Fixed TFA.
  • 4. Ballaset Cutters • Thermally Stable Polycrystalline (TSP) diamond cutters. • Extension of PDC cutter technology. • Cutter size expressed as stones per carat (SPC). Ballaset Cutters • Thermal stability allows cutters to be directly furnaced into the bit. • Developed for medium to hard applications, particularly carbonates. • Fixed Total Flow Area (TFA).
  • 5. Impregnated Cutters • Diamond grit is “hot- pressed” into tungsten carbide matrix to form impregnated segments. • Diamond grit is synthetic diamond material. Impregnated Cutters • Pre-formed segments furnaced directly into bit crown. • Grinding tool for very hard and abrasive applications. • Especially effective at high rotation speeds.
  • 6. Polycrystalline Diamond Compact Diamond Table Tungsten Carbide Substrate Conventional PDC Cutter PDC Cutter Sizes 0.750” - 19 mm 0.529” - 13.3 mm 0.323” - 8.2 mm 0.642” - 16 mm 0.315” - 8 mm 0.315” - 8 mm
  • 7. Sharp vs. Chamfered Cutting Action Failure Plane Failure Plane Polished Cutters Built-Up Edge Polished Cutter
  • 8. Carbide Supported Edge CSE Cutter Standard Cutter Tungsten Carbide Body Chamfer Angle Cutting Force CSE Geometry Strengthens The Diamond Edge Against The Cutting Force Materials & Bit Construction API Connection Stamp Area - Serial # - Style Nozzles - TFA - ND/Ballaset Junk Slot Breaker Slot Area Weld Blank Crown Chamfer Blank Blade Gauge Pad Matrix Body PDC Gauge Nozzle Cutters PDC Cutters Shoulder Cone Nose PDC Face Cutters
  • 9. Bit Profiles • Bit profile and cutter layout are closely related. • Layout is a compromise between the following: • Maximum number of cutters (longer bit life) • Lowest blade count (better hydraulics, penetration rate) • Shortest possible profile (better bit stability and cleaning) Volume of Rock Removed • Volume of rock removed is a function of • Cutter radius • Depth of cut • Width of cut • There is a direct relationship between the volume of rock removed and the work rate of a cutter.
  • 10. Volume of Rock Removed • The volume of rock 5 removed is calculated for a 4 given penetration rate Vorr (in3) 3 (depth of cut). 2 1 • We use profile and blade 0 count to manipulate the 1 2 3 4 Cutter # amount of work done in 60 RPM, 60 ft./hr each area of the bit. Blade Count & Cutter Density LIGHT MEDIUM HEAVY
  • 11. Blade Strength • Tapered blades provide optimum Blade strength and hydraulic efficiency Length • The blade strength is calculated Blade using the blade height, width, Height length and the leading edge root Blade Width radius. • Blade strength is given as a percentage of the API connection Root Radius strength. (i.e., 204%) Force Conventional Blade Configuration Backrake & Siderake
  • 12. Single Cutter Forces Depth of Cut F Torque Fn Fwob Fwob Fn Fs Fwob Fs • A cutter will see a different magnitude & direction of forces depending on it’s location on the bit profile. Resultant Cutter Force Vector Group #2 Group #2 Group #1 Group #1 Group #3 e Forc nce t Im bala Ne Group #4 Group #3 Group #4 Force Vector Groups Force Vector Summation
  • 13. Gauge Design • The gauge is considered the stabilizing, full hole section of a bit. • Gauge begins at the gauge point and continues up to the PDC Bit crown chamfer. Gauge • Typical materials include natural diamonds and tungsten carbide segments. • For optimum stability a flush set gauge pad is used. Anti-Whirl Force Balancing • Cutter layout & orientation are purposely designed to create a net imbalance force, pushing the bit against the hole wall and creating a stable rotating condition.
  • 14. PDC Applications 100,000 90,000 SEC PDC Application Limit 80,000 Standard PDC Limit 70,000 UCS (psi) 60,000 50,000 40,000 30,000 20,000 10,000 Quartzite Granite Marble Sandstone Limestone (metamorphic) (Igneous) (metamorphic) Marlstone IADC Dull Grading System Cutting Structure Bearing Gauge Comments Inner Outer Dull Location Bearing Gauge Other Reason Pulled Rows Rows Characteristic & Seal Characteristic X
  • 15. Cutter Wear Bit Dull / Other Characteristics BC - Broken Cone LT - Lost Teeth/Cutters BF - Bond Failure NR - Not Rerunnable BT - Broken Teeth/Cutters OC - Off-Center Wear BU - Balled Up PB - Pinched Bit CC - Cracked Cone PN - Plugged Nozzle/Flow Area CD - Cone Dragged RG - Rounded Gauge CI - Cone Interference RO - Ring Out CR - Cored RR - Rerunnable CT - Chipped Teeth/Cutters SD - Shirttail Damage ER - Erosion SS - Self-Sharpening Wear FC - Flat Crested Wear TR - Tracking HC - Heat Checking WO - Wash Out on Bit JD - Junk Damage WT - Worn teeth/Cutters LC - Lost Cone NO - No Other Major Dull LN - Lost Nozzle Characteristics
  • 16. Fixed Cutter Bit Profiles A - All over C - Cone - shown on all profiles N - Nose - Part of profile that would rest on the table if bit set upside down T – Taper – Straight portion tangent to nose and shoulder S - Shoulder - Outer area adjacent to the nose and gauge areas G - Gauge - Area ground to API specifications and cuts a “gauge” hole Worn Cutter
  • 17. Diamond Lip Worn Cutter
  • 18. Chipped Cutter Broken Cutters
  • 19. Lost Cutters Heat Checking
  • 20. Erosion Ring Out
  • 21. Junk Damage Cored
  • 22. Broken Blade Balled
  • 23. Plugged Nozzle Acknowledgement We wish to thank the Hughes Christensen division of Baker Hughes for their valuable assistance in the preparation of this material.
  • 24. Notes: __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________ __________________________________________________________