The document discusses various causes and prevention methods for stuck pipe while drilling. It covers solids induced pack-off, differential sticking, mechanical/wellbore geometry sticking, and inadequate hole cleaning. Key prevention strategies include maintaining proper mud properties, minimizing differential pressures, anticipating drilling hazards, and making wiper trips to clean the hole.

1. Stuck Pipe Prevention Prentice & Hill, LLC First Day

2. Hydrostatic Pressure Where: MW = Mud Weight (ppg) TVD = True Vertical Depth (ft) P = Hydrostatic Pressure (psi) MEMORIZE THIS EQUATION!!

3. Hole Volumes V = Hole Volume in BBL/FT D = Hole Diameter in INCHES

4. Pressure - Area Forces F = Force (lbs) P = Pressure (psi) A = Area (sq-in) F f = Force Due to Friction (lbs)  = Coefficient of Friction or Friction Factor F n = “Normal” Force (lbs)

5. Stuck Pipe Most Common “Trouble” in Overspent Wells Avoiding Stuck Pipe Understand Different Mechanisms Plan to Avoid Problems Recognize Symptoms Real Time Take Proper Actions While Drilling Use Recovery Procedures, if necessary

6. Solids Induced Pack-off Formation Movement Inadequate Hole Cleaning CAUSES

7. Solids Induced Pack-off Formation Loose w/ Little or No Bonding Insufficient Hydrostatic to Hold Back Formation UNCONSOLIDATED FORMATIONS Causes

8. Pack-off Due to Unconsolidated Formations Prevention Gel up Mud / Run Hi Vis Sweeps Control Drill Spot Gel Pill Prior to TOH Plan / Anticipate:

9. Solids Induced Pack-off Increase Mud Weight, if possible Use Under-saturated Water Base Mud Pump Fresh Water Sweeps Design Casing to Handle Collapse Loads Causes MOBILE / PLASTIC FORMATIONS Formation Extrudes Into Well Bore Due to Overburden Forces. Prevention Proper Well Planning:

10. Solids Induced Pack-off Causes Control Drill & Ream Connections Anticipate Reaming on Trips FRACTURED / FAULTED FORMATIONS Prevention Loose Chunks of Rock Fall into Well Bore Plan / Anticipate

11. Solids Induced Pack-off Causes Raise Mud Weight, if possible Set Casing Appropriately OVER-PRESSURED SHALE COLLAPSE Prevention Shale “Pops” Off Wall Due to Pressure Plan / Anticipate

12. Solids Induced Pack-off Causes Use Inhibited Mud System Minimize Exposure Time Be Prepared for “Gumbo Attack” REACTIVE FORMATIONS Prevention Mud Filtrate Reacts Chemically with Formation Plan / Anticipate

13. Solids Induced Pack-off Causes Increase Annular Velocities Better Mud Properties Subject of another section POOR HOLE CLEANING Prevention Not Removing Cuttings From Well Bore

14. Differential Sticking Causes High Differential Pressures Excessive Mud Weight Drawn Down Formations Poor Well Planning Well Bore Contact Poor Filter Cake Little or No Pipe Motion

15. Bad Filter Cake

16. Differential Sticking - Prevention Minimize Mud Weight Improve Filter Cake Select Proper Casing Seat Minimize Contact Area Stabilizers Heavy Weight Drill Pipe Spiral Drill Collars Keep Pipe Moving Plan / Anticipate

17. Mechanical / Wellbore Geometry Sticking Causes KEYSEATING Minimize Dog Leg Severity Case Off Curves Soon After Building Use Keyseat Wiper Make Frequent Wiper Trips Back Ream Out of Hole Abrupt Change in Well Bore Path (Dog Leg) Long Hole Section Below Dog Leg Prevention

18. Mechanical / Wellbore Geometry Sticking Causes UNDERGAUGE HOLE Always Gauge Bit & Stabilizers IN and OUT Run Gauge Protected Bits & Stabilizers Ream Suspected Undergauge Sections Undergauge Bit and/or Stabilizers Coring (Core heads slightly U.G.) Prevention

19. Mechanical / Wellbore Geometry Sticking Causes LEDGES & DOGLEGS Run Packed Hole Assemblies Ream on Trips Through Problem Zones Limber BHAs Hard - Soft Interbedded Formation Prevention

20. Mechanical / Wellbore Geometry Sticking Causes SHOE JOINT BACKS OFF Do Not Overdisplace Cement Thread Lock Bottom 3 Joints of Casing Drill Out Carefully Prevention

21. Mechanical / Wellbore Geometry Sticking Causes GREEN CEMENT Wash Down Carefully to “Top of Cement” Pre-Treat Mud Before Drilling Green Cement Prevention Run BHA Into Un-set Cement

22. Mechanical / Wellbore Geometry Sticking Causes JUNK Good Housekeeping on Rig Floor Keep Hole Covered Inspect Equipment Frequently Prevention Something Manmade is Loose in the Hole

23. Mechanical / Wellbore Geometry Sticking Causes CEMENT BLOCKS Set All Casing As Close To TD As Possible Ream Casing Shoe & Open Hole Plugs Before Drilling Ahead Hard Cement Falls In From Casing Shoe or From Open Hole Cement Plug Prevention

24. Mechanical / Wellbore Geometry Sticking Causes LINER & SQUEEZE CEMENTING Hazards in Liner Cementing Too Much Excess Overdisplacement Squeeze Cementing Hold Pressure on Back Side, If Possible Use Cement Retainers DO NOT Cement Up a Squeeze Packer (RTTS) Cementing Yourself in the Hole

25. MUD Mud Types / Constituents Water Base Mud Oil Base Mud Synthetic Base Mud Primary Functions (Review) Remove Cuttings Lubricate and Cool Bit Provide Hydrostatic

26. Mud (continued) Filter Cake “2/32” Fluid Loss API Fluid Loss Room Temperature 100 psi differential

27. Mud Filter Press

30. Mud (continued) Filter Cake “2/32” Fluid Loss API Fluid Loss Room Temperature 100 psi differential High Temperature, High Pressure (HTHP) 300º F or as specified 500 psi differential

34. Mud (continued) Rheological Properties Measured with Fann Viscometer Funnel Viscosity Plastic Viscosity Yield Point

37. Mud (continued) Mud Additives Gel (Wyoming Bentonite) Barite Chemicals Lost Circulation / Stuck Pipe Preventatives Sized Particulate Matter Fibrous Material Asphalt Snake Oil

38. Influence of Mud Properties on Various Stuck Pipe Mechanisms

39. Inadequate Hole Cleaning Near Vertical Wells (Incl < 30 deg) Stabilize Hole Maintain Good Annular Velocity Keep Low Shear Rate Viscosities High Yield Stress = 2 (  6 -  3 ) Gel Strength Do Not Overload Hole Due to Too High ROP Clean Hole Prior to Trip

40. Inadequate Hole Cleaning Most Difficult Angle to Clean Hole Unstable Cuttings Beds Form Beds May Avalanche Even With Pumps On Raising Mud Viscosity Alone Will Not Solve M-I Video of Hole Cleaning Moderate Angle Wells (30° <Incl < 60°)

41. Inadequate Hole Cleaning Moderate Angle Wells (30° <Incl < 60°) Anticipate Problem - Alert for Symptoms Erratic Pump Pressure Reduced Returns at Shaker for ROP Erratic PWD Data Increasing Overpull 5-10 Stands Off Bottom It Is Possible to Get Stuck In Cased Hole Problem Prevention

42. Inadequate Hole Cleaning Moderate Angle Wells (30° <Incl < 60°) Take Preventive Actions Agitate Cuttings Beds Rotate DP at 150+ RPM if possible Reciprocate & Rotate While Circulating Bottoms Up Maximize Annular Velocity Larger Drill Pipe Larger Jets Make Wiper Trips Back Ream Out Of Hole - Carefully! Problem Prevention

43. Inadequate Hole Cleaning High Angle Wells (Incl > 60°) Cuttings Beds Form, But Are Stable Hole Cleaning Usually Not A Problem in High Angle Section Cuttings Beds Potential Problem on Trips Back Ream Out of High Angle Section Reminder - All High Angle Wells Have a Moderate Angle (Problematic) Section Problem Prevention

44. Inadequate Hole Cleaning Causes Inadequate Mud Flow Properties Too Low an Annular Velocity Cuttings Beds in Directional Holes Angle < 30º - Minimal Problems Angle > 60º - Minimal Problems 30º < Angle < 60º Problem Area

45. Inadequate Hole Cleaning Prevention Keep Mud in Good Shape Watch Shale Shaker for Too Few Cuttings Pump More Fluid (Increase AV) Run High / Low Viscosity Sweeps Use Larger Drill Pipe Avoid long 30º to 60º Angle Sections Make Wiper Trips (Ream Out w/ Top Drive)