1 / 24

Testing and Modeling Approach for Underbalance Effects in Perforation

This study utilizes laboratory testing and numerical modeling to understand the effects of static and dynamic underbalance on perforation clean-up and optimize perforated completion strategies.

abates
Download Presentation

Testing and Modeling Approach for Underbalance Effects in Perforation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. IPS – 15 - 10 2015 International Perforating Symposium Europe The Renaissance Hotel, Amsterdam 19th - 21stMay 2015 An Integrated Testing and Modeling Approach to Understand the Competing Effects of Static vs. Dynamic Underbalance Graham Fraser, Tullow Oil Noma Osarumwense, Baker Hughes Rajani Satti, Baker Hughes

  2. Outline IPS – 15 - 10 • Introduction • - Background • - Objectives • - Deepwater Well Description • - Design Philosophy • Perforation Flow Laboratory • - Description • - Test Configuration/Matrix • Experimental Results • Computational Modeling • Conclusions

  3. Background IPS – 15 - 10 • Focus of this study is to exploit laboratory-based testing • as well as reliable modeling to design and optimize • perforated completion strategies. • The objectives of this study are therefore, three-fold: • Utilize the flow laboratory to provide a better understanding of shaped charge perforating/performance • Effect of underbalance/overbalance • Zinc vs steel case • Understand the effects of Static and Dynamic Underbalance on Perforation Clean up • Gain insight into how numerical modeling can be used to complement experiments.

  4. Well Description IPS – 15 - 10 • Offshore West Africa • 1000 m – 1980 m water depth • Sandstone reservoir • Natural completion • Typical Well Data • Reservoir depth: 3300 – 3600 mTVD • Reservoir pressure: 6300 – 6412 psi • Formation fluid : Oil ( 33o – 35o API) • Permeability : 200 – 600 md • Porosity : 14 – 21% • Temp: 200 – 230°F • Bore Hole Size: 12.25 inch. • Casing Size : 9-5/8 inch.

  5. Design Philosophy IPS – 15 - 10 Integrated Engineering Workflow that combines experimental and numerical methods to develop perforating solutions and optimize pay zone productivity

  6. Perforation Flow Laboratory IPS – 15 - 10 • API Recommended Practice 19B Section-II and IV testing. • Provides the capabilities to: • Study and qualify the performance of different perforating systems in formation rock at reservoir conditions • Study the influence of various factors on well productivity • Integrate this knowledge to select the optimal perforating system and clean up strategy for improved productivity.

  7. IPS – 15 - 10 Perforation Flow Measurements • Pre-shot porosity • UCS from Scratch testing • Pre/post perforation permeability • Perforation tunnel diameter • Perforation tunnel depth • Detailed tunnel characterization using advanced CT scanning methods • Dynamic pressure data • Core flow efficiency and productivity ratio • Evaluate perforation cleanup mechanisms • Optimization of underbalance methods

  8. Test Configuration IPS – 15 - 10 • Three Charge Types • 39 gm steel case DP, HMX • 39 gm zinc case DP, HMX • 39 gm steel case Ultra DP, HMX • Rock Type: Buff Berea • Permeability: ~ 200 mD • UCS: ~ 4000 psi • Average Porosity: 22% • Confining pressure : 9,300 psi • Pore pressure: 6,000 psi

  9. IPS – 15 - 10 Test Matrix • Effect of underbalance conditions • Overbalanced (250 psi) with minimum Dynamic Underbalance • Static Underbalance (500 psi) with Dynamic Underbalance • Higher Static Underbalance (2,000 psi) with Standard Gun Volume • Higher Static Underbalance (2,000 psi) with Dynamic Underbalance • Performance comparison of steel vs. zinc case charges

  10. Results IPS – 15 - 10 Effect of Dynamic Underbalance CT Scanner Lab CT scan, and split core images

  11. IPS – 15 - 10 Results Effect of Underbalance Conditions * Penetration Length includes the narrow extended tip (see CT Scan image in next slide)

  12. Results IPS – 15 - 10 CT Image – 2044 CT Image – 2036 Core Penetration (in.) 500psi UB, 615 cc GV 2000psi UB, 615cc GV 250psi OB 100cc GV 2000psi UB, 585cc GV CT Image - 2050 CT Image – 2045 DUB Achieved (psi) CT Scan and Split core images 2000psi UB, 615cc GV 2000psi UB, 585cc GV 250psi OB 100cc GV 500psi UB, 615cc GV

  13. Results IPS – 15 - 10 • The 2,000psi and 500psi static underbalance cases indicate higher flow efficiency, uniformly larger perforation tunnel along its length, and a larger entry hole diameter in the core. • The case with 2,000psi static underbalance yielded the highest penetration length* • Dynamic pressure data shows that static underbalance affects the magnitude of dynamic underbalance achieved. * Penetration Length includes the narrow extended tip (see CT Scan image)

  14. IPS – 15 - 10 Results 2. Performance of Shaped Charges (steel vs. zinc case)

  15. IPS – 15 - 10 Results Core Penetration (in.) Split Core - Zinc case charges Zinc Split Core - Steel case charges • Depth of penetration and magnitude of dynamic underbalance is higher with the steel charges. • Dynamic Underbalance is achieved with zinc case charges. DUB Achieved (psi) Zinc Zinc Steel Steel

  16. IPS – 15 - 10 Wellbore Dynamics Modeling Industry leading software platform for computational modeling of transient, downhole perforating events. • Scientific code capable of simulating short-time dynamic events in the coupled wellbore-perforation-fracture-reservoir system. • Application space of perforation / stimulation jobs • Flexible input for tooling and conveyance

  17. Wellbore Dynamics Model: Physics Incorporates complex full-physics models to model full-scale dynamic perforating events

  18. IPS – 15 - 10 Transient Pressure Comparisons Recorded data from High Speed Gauge Recorded data from High Speed Gauge Calculated data from Model Calculated data from Model Recorded data from High Speed Gauge Calculated data from Model

  19. IPS – 15 - 10 Effect of Static UB on Dynamic UB

  20. IPS – 15 - 10 Effect of Static UB on Dynamic UB

  21. Field Run Comparison (Initial Overlay: Modeled vs. Actual) IPS – 15 - 10 • Typical Well Data • Well Type: 2 - Zone Gas Injector • Water Depth: • Reservoir Depth: 3856 m MD • Reservoir Pressure: 5892 - 5905psi • Permeability : 33.55 md– 454.06md • Porosity : 17 – 20% • Temp: 211 – 213°F • Bore Hole Size: 12.25 inch. • Casing Size : 9-5/8 inch. • Well Condition: Balanced • Gun System: 7 inch x 39gm x 135/45 • deg x steel case DP, HMX Calculated data from Model Recorded data from High Speed Gauge

  22. IPS – 15 - 10 Conclusions • Perforation tunnel characteristics, cleanup and flow performance were better with the static underbalance conditions compared to the overbalance with minimum dynamic underbalance condition as seen in the experimental results. • The magnitude of dynamic underbalance achieved decreases with increase in static underbalance (as seen from both experiments/modeling). Further modeling efforts are underway to understand this complex phenomenon. • Dynamic Underbalance is indeed achieved with zinc case charges. However, penetration depth and the magnitude of dynamic underbalance achieved is higher with the steel case charges.

  23. Slide 23 IPS – 15 - 10 Acknowledgements / Thank You • Management of Tullow Oil and Baker Hughes for supporting this study. • Committee of the 2015 IPS Europe for giving us the opportunity to present this work.

  24. Slide 24 IPS – 15 - 10 Questions ?

More Related