Relief Well Ranging Strategy

Transcription

1 Relief Well Ranging Strategy L. Wm Bill Abel ABEL Engineering LLP Houston, Texas USA 1

2 Relief Well History Santa Barbara oil spill occurred in January 1969 in the Santa Barbara Channel in Southern California According to Dr. Preston Moore the first relief well ever was for this problem and the objective was to penetrate and produce the reservoir to blowdown the pressure and thus stop the flow, e.g., RELIEF WELL relieved the pressure in the reservoir. 2

3 Why do we drill relief wells? Answer: Because we have to! If there is another solution, it is taken because time is the driving factor in any well control event. SOLUTION MUST BE SOONER RATHER THAN LATER IN ALL CASES. 3

4 GOM Event 2007 Off-bottom Kill Objective 4

5 N. America HTHP Land 5

6 Lake Maracaibo crater circa

7 Swamp Barge Rig Marea after a few hours of exposure to fire 7

8 Dewi9 on TNE5 with RW in the background Big crocodiles! 8

9 How Does Ranging Fit Into the Project RELIEF WELL TEAM WELL PLANNING PROXMINITY LOGGING (Ranging Runs) FLOW ASSURANCE / HYDRAULIC MODELING Survey Mgt. INTERCEPTION / COMMUNICATION DIRECTIONAL DRILLING / MWD-LWD LWA Aug-10 9

10 Overlapping responsibilities Well Plan Project Engineering "Relief Well Team" Proximity Logging Hydraulic Simuation Interception Stragegy Directional Drilling 10

11 + Corporate Image Incident begins - OVER ALL OBJECTIVE STOP THE FLOW STABILIZE THE WELL Quality of Press Releases with pre-plan Image with a pre-plan Image sans pre-plan Flow stopped Time Savings Quality of Press Releases sans pre-plan??? Flow stopped Time + Quality of Press Releases - 11

12 IMPACT OF TIME Flow stopped Pre-Plan BCP Cost of Control Pre-Planned Project Curve POLLUTION / PRODUCTION LOST Normal Project Curve Flow stopped Time Savings Pollution stopped Pollution stopped Pollution saved Cost Savings Produciton Lost / Pollution Incident begins Time 12

13 OBJECTIVES Allow communication for a pump to kill operation Least risk per ALARP (as low as reasonably possible) Least time possible (time = exposure in blowout) 13

14 The real Objective Hit a VERY small target and make a communication: 14

15 Proximity Choices: WL (active) or MWD (passive) Why choose one over the other? Both have strength and weaknesses Active has greater range (in most cases) Passive uses tools that are already in the hole (MWD) no trip out to obtain data (provided you are within the detection range) LOGICAL ANSWER: Use both 15

16 Relief Well Plans are now part of the Emergency Response Plan ERP for high risk (pollution) 16

17 Angle Impact (Incident and EOUs size) 17

18 TVD MD Ple-10 Relief Well Trajectory Large KOP Incident ANG = 44.0 Angel Small End Bld EOUs X Target MD TD TD TVD X Deprt EOU Ple-10 RW , ,091.4 uated LWA Sept

19 Low Incident Angle Large EOUs 19

20 Ranging in small EOU 2m 2m Blowout Well Well Separation 10 12m ' vendor MWD Proximity Range Relief Well 8m 7m MWD Proximity Range 24m (diameter) Sum of Surface + RW + Blowout Well Uncertainty 28m (diameter) Change in azimuth MWD Proximity MWD Range Proximity MWD Proximity MWD Range Proximity Range Range MWD MWD Proximity Proximity Range Range 24m (diameter) 24m (diameter) 24m (diameter) 24m (diameter) 24m (diameter) 24m (diameter) Sweeping thru the ellipse to locate Blowout Well Casing 20

21 Large Incident AZ well AZ small EOUs 54m 36m 1590m MD 29.8 x 12m 57m m TVD 54m well AZ RW AZ m Active AZ m 54m 54m 1590m MD highside well AZ m Passive 36m 84 lowside 36m 29.8 x 14.8m m TVD 38m. OPEN HOLE POTENTIAL UNPLANNED COMMUNICATION LWA Sept

22 Small EOU but high Incident angle Passive 9-5/8" 43.5 lbs/ft Major Axis x 9-5/8" Casing Shoe 118 x 46m Active 35 deg Incident angle RW Gyro Major Axis x Intercept 37 x 24m 30.6m 19m EOU Combined Major Axis x 9-5/8" Casing Shoe 155 x 70m 43.6m Gryo Major Axis x Intercept 19.6 x 14.4m Passive 9-5/8" 43.5 lbs/ft 30.6m 19m Major Axis x 9-5/8" Casing Shoe x 19m EOU Combined Major Axis x 9-5/8" Casing Shoe 165 x 23.4m 43.6m LWA Sept-15 Active 35 deg Incident angle 22

23 Blowout well (Target) LWD/MWD Ranging Relief well LWD/MWD tool range Trace across the ellipse of uncertainty Ellipse of uncertainty Calculated well location Actual well location R 2 R 1 1 Investigated area Area left to investigate Detection point Well Planning Extends Range-of-Detection Intercept and communication point 23

24 Sweep thru the EOU holding angle mtvd 30.6m 19m 19.4m x 45.2m Maj x Vert 30.6m 19m 30.6m 19m 1205 mtvd mtvd 30.6m 19m x 52.2m 30.6m 19m 30.6m 19m 15.3m. 1267m TVD Major x Vertical x 59m 1267 mtvd 30.6m 19m 30.6m 19m 1282 mtvd 24

25 Example Strategy for Ranging 0 (RT) 500 KOP 642m 1 0 /10m AZ RW Phase 8-¼ Phase Blowout Vertical section Blowout Well NOTE: Hold trajectory is maintained until casing is detected with proximity logs. MWD Ranging at 50m separation Detection, mapping of relative position SEE NOTE MWD Bit Sub Anticollision Hold AZ Inc 81 0 Line up to parallel AZ Nudge away if needed to avoid unplanned collision Match AZ and 4 to 7 m separation Check shots Check shots End far side of EOU AZ Inc /8" 9-5/8" Case well after lined up to hit Line up to intercept attack angle Drill out with slim BHA and hit well to communicate PUMP TO KILL WELL CONTROLLED 25

26 ABEL Generalized Ranging Strategy Aim at a point where the EOU is manageable (not all that big if possible) Use near-bit inc. and MWD as anticollision and ranging Drill to that point where calcs say detection should have happened If no go Log the hole with WL and or EMS run or continuous MWD to increase detection range 26

27 USE DEMMING MODEL Assess risks v. benefits Evaluate Available Resources Determine Possible Actions Identify Actions Identify personnel roles Determine desired activities Request resources` Emergency Event Identify Real Problems Get It Done Hazards to people/environment? Damage to property Incident Response Needs Timeframe No Improve future response capabilities Monitor Results Problem Solved? Yes Stop work & record activities Use ICS systems Ensure safety of personnel Communicate Actions Clearly 27

28 END OF PRESENTAION HTHP Land N. America