Forage et complétion de puits

Coiled Tubing Drilling

Forage avec tubing enroulé : une approche flexible et polyvalente

Le forage avec tubing enroulé (CTD) est une technique de forage spécialisée qui utilise une longueur continue de tubing enroulé comme colonne de forage principale. Ce tubing flexible, généralement en acier à haute résistance, est logé sur un large tambour et introduit dans le puits au fur et à mesure des besoins. Le processus de forage est piloté par un moteur à boue ou, moins fréquemment, un moteur électrique, qui fait tourner le trépan situé à l'extrémité du tubing enroulé.

Caractéristiques clés du forage avec tubing enroulé :

  • Flexibilité : La flexibilité du tubing enroulé lui permet de naviguer dans des géométries complexes de puits, y compris des courbes serrées et des déviations, ce qui le rend idéal pour le dérapage, la réentrée et l'accès à des formations difficiles à atteindre.
  • Forage sous-équilibré : Le CTD est souvent utilisé pour le forage sous-équilibré, une technique où la pression dans le puits est maintenue en dessous de la pression de la formation. Cela peut contribuer à améliorer le contrôle du puits, à stimuler la formation et à réduire les dommages à la formation.
  • Empreinte plus petite : Par rapport aux plates-formes de forage conventionnelles, les opérations CTD nécessitent une empreinte plus petite et sont souvent plus mobiles, ce qui les rend adaptées aux endroits éloignés et aux environnements difficiles.
  • Opérations multiples : Le CTD peut effectuer une large gamme d'opérations au-delà du forage, y compris la stimulation du puits, le cimentation et les interventions de travaux de réparation.

Avantages du forage avec tubing enroulé :

  • Contrôle amélioré du puits : La nature flexible du tubing enroulé permet un contrôle précis du trépan, minimisant le risque d'instabilité du puits et d'afflux de fluide incontrôlé.
  • Stimulation de la formation améliorée : Le forage sous-équilibré, souvent utilisé dans le CTD, peut améliorer considérablement la stimulation du réservoir, conduisant à des taux de production plus élevés et une meilleure récupération du pétrole et du gaz.
  • Réduction des coûts de forage : La plus petite empreinte des équipements et les temps de mobilisation plus rapides peuvent conduire à des coûts de forage plus bas.
  • Sécurité accrue : Les techniques CTD utilisent souvent des diamètres de puits plus petits, réduisant le risque d'effondrement du puits et augmentant la sécurité pendant les opérations de forage.

Applications du forage avec tubing enroulé :

  • Dérapage : Le CTD est très efficace pour les opérations de dérapage, permettant de forer de nouveaux puits à partir de puits existants pour accéder à de nouvelles zones de réservoir ou éviter les problèmes de puits existants.
  • Réentrée : Le CTD est idéal pour accéder aux puits abandonnés ou bouchés, facilitant la réentrée du puits et la reprise de la production.
  • Stimulation du puits : Le CTD peut être utilisé pour effectuer diverses techniques de stimulation du puits, notamment l'acidification, la fracturation et la consolidation du sable, afin d'améliorer la productivité du puits.
  • Interventions de travaux de réparation : Le CTD est un outil polyvalent pour les travaux de réparation de puits, notamment le remplacement ou la réparation du tubing, le nettoyage des débris et la réalisation d'autres tâches de maintenance.

Défis du forage avec tubing enroulé :

  • Limites de profondeur : Le CTD est généralement limité à des profondeurs inférieures à 10 000 pieds en raison des limites de longueur et de poids du tubing enroulé.
  • Nettoyage du trou : Le maintien d'un bon nettoyage du trou dans les opérations CTD peut être difficile en raison du plus petit diamètre de la colonne de forage et des débits potentiellement plus faibles.
  • Couple et traînée : Le tubing enroulé peut subir un couple et une traînée importants, en particulier dans les puits déviés ou complexes, nécessitant une planification et une exécution minutieuses pour minimiser ces problèmes.

Conclusion :

Le forage avec tubing enroulé offre une approche unique et flexible du développement des puits, offrant des avantages importants dans des applications spécifiques. Sa capacité à naviguer dans des géométries de puits difficiles, à améliorer la stimulation de la formation et à effectuer une variété d'opérations en fait un outil important pour l'industrie pétrolière et gazière. Bien que des défis existent, les progrès technologiques continus continuent d'étendre la portée et les capacités du CTD, assurant sa pertinence continue dans l'avenir des opérations de forage.

Test Your Knowledge

Coiled Tubing Drilling Quiz

Instructions: Choose the best answer for each question.

1. What is the primary advantage of using coiled tubing in drilling operations?

a) It's cheaper than traditional drill pipe. b) It can drill deeper wells than traditional drill pipe. c) It offers flexibility to navigate complex wellbore geometries. d) It's more efficient for drilling horizontal wells.

Answer

c) It offers flexibility to navigate complex wellbore geometries.

2. Which of the following drilling techniques is often employed with coiled tubing drilling?

a) Balanced drilling b) Underbalanced drilling c) Overbalanced drilling d) Horizontal drilling

Answer

b) Underbalanced drilling

3. What is a key benefit of using underbalanced drilling in CTD?

a) It reduces the risk of wellbore collapse. b) It helps to improve formation stimulation. c) It minimizes the need for wellbore cementing. d) It increases drilling speed.

Answer

b) It helps to improve formation stimulation.

4. Which of the following is NOT a typical application of coiled tubing drilling?

a) Sidetracking b) Re-entry c) Well stimulation d) Deepwater drilling

Answer

d) Deepwater drilling

5. What is a major challenge associated with coiled tubing drilling?

a) The inability to drill horizontal wells b) The high cost of coiled tubing c) Maintaining good hole cleaning d) The risk of wellbore instability

Answer

c) Maintaining good hole cleaning

Coiled Tubing Drilling Exercise

Scenario: You are working on a project to re-enter an abandoned well using coiled tubing drilling. The well has been plugged for 10 years and is expected to have significant build-up of debris. You need to design a plan for re-entry and wellbore clean-up using CTD.

Tasks:

  1. Identify the main challenges you may encounter during this operation.
  2. Propose specific CTD techniques and tools that can be used to effectively clean the wellbore and remove any blockages.
  3. Outline a step-by-step procedure for the re-entry and wellbore clean-up operation using CTD.

Exercice Correction

**1. Challenges:** * **Debris removal:** The wellbore may be filled with debris, including scale, sand, and potentially even cement. Removing these blockages will require specialized tools and techniques. * **Corrosion:** The wellbore may have corroded due to inactivity, leading to potential wellbore instability and collapse. * **Wellbore Integrity:** The condition of the wellbore casing, tubing, and other components may be compromised, requiring careful inspection and potential repairs. **2. CTD Techniques and Tools:** * **Jetting:** Using high-pressure fluid jets to dislodge and remove debris. * **Mechanical Milling:** Employing specialized cutters or milling tools to break up and remove debris. * **Swabbing:** Using specialized tools to lift and remove debris from the wellbore. * **Wireline Logging:** Performing logging runs to assess the wellbore condition and identify the location of debris. * **Wellbore Cleaning Fluid:** Using specialized fluids to help dislodge and remove debris, while also minimizing potential corrosion and wellbore damage. **3. Step-by-Step Procedure:** 1. **Initial Assessment:** Conduct a thorough inspection and evaluation of the abandoned well using available data and logs. 2. **Wellbore Integrity Check:** Run a wireline logging tool to assess the condition of the casing and tubing, identify potential blockages, and evaluate the wellbore integrity. 3. **Re-entry Operation:** Deploy the coiled tubing unit and carefully re-enter the wellbore. 4. **Debris Removal:** Utilize a combination of jetting, milling, and swabbing techniques to remove the debris from the wellbore. 5. **Fluid Circulation:** Circulate cleaning fluids through the wellbore to remove any remaining debris and ensure good wellbore cleaning. 6. **Wellbore Integrity Verification:** Repeat wireline logging runs to confirm the effectiveness of the cleaning operation and verify the wellbore integrity. 7. **Completion and Production:** Once the wellbore is cleaned and the wellbore integrity is confirmed, proceed with the desired completion operation and production activities.

Books

  • Coiled Tubing Drilling and Workover Operations by Robert A. Green (This is a comprehensive guide covering all aspects of CTD operations)
  • Well Intervention Techniques: A Practical Guide by John L. Adams and John H. Lee (Includes a dedicated section on CTD with emphasis on practical applications)
  • The Petroleum Exploration & Production Handbook by John M. Campbell (Offers a chapter on drilling techniques, including CTD)

Articles

  • "Coiled Tubing Drilling: A Comprehensive Review" by D.K. Shukla and S. K. Srivastava (Journal of Petroleum Science and Engineering, 2010): Provides a detailed overview of the technology and its applications.
  • "Coiled Tubing Drilling and Its Applications in Unconventional Reservoirs" by H. Al-Otaibi, et al. (SPE Journal, 2016): Focuses on the use of CTD in unconventional resource development.
  • "Optimizing Coiled Tubing Drilling Operations: A Case Study" by M. A. Ghasemi and H. A. Jafarian (Journal of Natural Gas Science and Engineering, 2017): Highlights practical aspects of optimizing CTD operations.

Online Resources

  • Society of Petroleum Engineers (SPE): Search their website for articles, papers, and presentations related to CTD.
  • Coiled Tubing Institute (CTI): This organization provides information, training, and resources related to coiled tubing technology.
  • Oil & Gas Journal (OGJ): Search their website for articles and news related to CTD.
  • Drilling & Completion magazine: Offers articles and technical discussions on drilling techniques, including CTD.

Search Tips

  • Use specific keywords: "Coiled Tubing Drilling", "CTD", "Underbalanced Drilling", "Well Stimulation", "Sidetracking", "Re-entry", "Workover".
  • Combine keywords with specific applications: "Coiled Tubing Drilling Shale Gas", "CTD Horizontal Wells", "Underbalanced Drilling Tight Formations".
  • Include specific company or project names: "ExxonMobil Coiled Tubing Drilling", "CTD in the Permian Basin".
  • Use advanced search operators: "+" to include a specific word, "-" to exclude a word, "" to search for an exact phrase, "site:spe.org" to limit search to a specific website.

Techniques

Chapter 1: Techniques in Coiled Tubing Drilling

This chapter delves into the various techniques employed in coiled tubing drilling (CTD), providing a comprehensive overview of the key aspects of this specialized drilling method.

1.1 Drilling with Coiled Tubing:

  • Continuous Tubing: CTD utilizes a continuous length of coiled tubing, typically housed on a large drum. As the drill string progresses downhole, the tubing is uncoiled from the drum and fed into the wellbore.
  • Drilling Mechanisms: The drilling process is typically driven by a mud motor, although electric motors are sometimes used. The mud motor is attached to the end of the coiled tubing and rotates the drill bit.
  • Underbalanced Drilling: CTD is often employed for underbalanced drilling, where the pressure inside the wellbore is lower than the formation pressure. This technique enhances formation stimulation and reduces the risk of formation damage.

1.2 Coiled Tubing Operations Beyond Drilling:

  • Well Stimulation: CTD plays a critical role in well stimulation, facilitating operations like acidizing, fracturing, and sand consolidation, aimed at improving well productivity.
  • Cementing: Coiled tubing can be used to perform cementing operations, including wellbore isolation and zonal control.
  • Workover Interventions: CTD is a versatile tool for well workovers, such as replacing or repairing tubing, cleaning out debris, and performing other maintenance tasks.

1.3 Key Considerations in Coiled Tubing Operations:

  • Hole Cleaning: Effective hole cleaning is crucial in CTD due to the smaller drill string diameter and potential lower flow rates. Specialized techniques and equipment are used to ensure efficient debris removal.
  • Torque and Drag: Coiled tubing can experience significant torque and drag, particularly in deviated or complex wellbores. Careful planning and execution are required to minimize these issues.
  • Wellbore Control: The flexible nature of coiled tubing allows for precise control over the drill bit, reducing the risk of wellbore instability and uncontrolled fluid influx.

1.4 Conclusion:

CTD techniques are highly versatile, providing a flexible and effective solution for a wide range of drilling and wellbore operations. Understanding these techniques is essential for optimizing well performance and maximizing hydrocarbon recovery.

Chapter 2: Models and Applications of Coiled Tubing Drilling

This chapter explores various models and applications of coiled tubing drilling (CTD), highlighting its strengths and limitations in specific scenarios.

2.1 Coiled Tubing Drilling Models:

  • Continuous Coil Model: This is the most common model, where a continuous length of coiled tubing is used as the drill string. It is highly flexible and allows for navigating complex wellbore geometries.
  • Split-Coil Model: In this model, two or more sections of coiled tubing are joined together to extend the reach of the drill string. This allows for drilling deeper wells compared to the continuous coil model.
  • Hybrid Models: These models combine elements of both the continuous coil and split-coil models, offering flexibility and extended reach.

2.2 Applications of Coiled Tubing Drilling:

  • Sidetracking: CTD is highly effective for sidetracking operations, allowing for the drilling of new wellbores from existing ones to access new reservoir zones or avoid wellbore problems.
  • Re-entry: CTD is ideal for accessing abandoned or plugged wells, facilitating wellbore re-entry and resuming production.
  • Horizontal Drilling: CTD can be used for drilling horizontal wells, particularly in tight formations where conventional drilling methods are impractical.
  • Directional Drilling: CTD allows for precise directional drilling, navigating complex wellbore geometries and optimizing reservoir contact.

2.3 Limitations of Coiled Tubing Drilling:

  • Depth Limitations: CTD is typically limited to depths of less than 10,000 feet due to the limitations of coiled tubing length and weight.
  • Hole Cleaning Challenges: Maintaining good hole cleaning in CTD operations can be challenging due to the smaller drill string diameter and potentially lower flow rates.
  • Torque and Drag Issues: Significant torque and drag can occur in deviated or complex wellbores, requiring careful planning and execution to minimize these problems.

2.4 Conclusion:

Coiled tubing drilling offers a unique and adaptable approach to wellbore development, suitable for various applications and scenarios. Its flexible nature, ability to navigate challenging wellbore geometries, and suitability for underbalanced drilling make it a valuable tool in the oil and gas industry. However, understanding its limitations and selecting appropriate models are crucial for successful CTD operations.

Chapter 3: Software and Technology in Coiled Tubing Drilling

This chapter explores the software and technology used in coiled tubing drilling (CTD) operations, examining their role in optimizing efficiency, safety, and wellbore performance.

3.1 Coiled Tubing Simulation Software:

  • Wellbore Trajectory Simulation: Software programs simulate wellbore trajectory, considering factors like wellbore geometry, drilling fluid properties, and coiled tubing characteristics.
  • Torque and Drag Analysis: Simulation software analyzes and predicts potential torque and drag issues, aiding in optimizing CTD operations and minimizing equipment wear.
  • Hole Cleaning Simulation: Software programs simulate hole cleaning efficiency, helping operators adjust drilling parameters and optimize fluid circulation for effective debris removal.

3.2 Downhole Tools and Technology:

  • Mud Motors: Advanced mud motors with enhanced performance and durability are used to drive the drill bit and optimize drilling efficiency.
  • Coiled Tubing Connectors: Specialized connectors ensure secure and leak-proof connections between coiled tubing sections, enhancing safety and reliability.
  • Telemetry Systems: Real-time data collection and transmission systems provide operators with critical information about downhole conditions, enabling informed decision-making.

3.3 Automation and Robotics:

  • Automated Control Systems: Advanced automation systems improve precision and efficiency in coiled tubing operations, reducing human error and enhancing safety.
  • Robotics Applications: Robotic systems are being explored for specialized tasks like wellbore inspection, downhole intervention, and tool deployment.

3.4 Future Trends in Coiled Tubing Technology:

  • Lightweight Coiled Tubing: Development of lighter and more robust coiled tubing materials to increase depth capabilities and improve drilling efficiency.
  • Enhanced Hole Cleaning Techniques: Exploration of advanced hole cleaning tools and techniques to overcome limitations associated with smaller drill string diameters.
  • Integration of Artificial Intelligence: Incorporating AI into CTD operations to optimize decision-making, predict potential problems, and improve well performance.

3.5 Conclusion:

Software and technology play a vital role in modern coiled tubing drilling operations. These tools enable operators to simulate wellbore conditions, analyze potential issues, optimize drilling parameters, and improve overall efficiency and safety. Advancements in technology continue to expand the capabilities of CTD, leading to more effective and efficient drilling operations.

Chapter 4: Best Practices in Coiled Tubing Drilling

This chapter explores key best practices for optimizing coiled tubing drilling (CTD) operations, encompassing various aspects from planning to execution.

4.1 Planning and Preparation:

  • Thorough Wellbore Characterization: Accurate wellbore geometry, formation properties, and geological data are crucial for planning effective CTD operations.
  • Rig Selection and Equipment Optimization: Choosing the right rig with appropriate equipment for the specific well and operations is critical for successful CTD execution.
  • Drilling Fluid Selection: Selecting the right drilling fluid with suitable properties for wellbore stability, hole cleaning, and formation protection is essential.
  • Safety Procedures and Emergency Response: Implementing comprehensive safety protocols and training personnel for emergency response are paramount for safe CTD operations.

4.2 Execution and Monitoring:

  • Continuous Monitoring and Data Analysis: Real-time monitoring of downhole conditions and data analysis are crucial for making informed decisions during CTD operations.
  • Effective Hole Cleaning: Utilizing proper techniques and equipment for efficient hole cleaning is essential to prevent drill string sticking, formation damage, and lost circulation.
  • Torque and Drag Management: Careful planning and execution are necessary to minimize torque and drag issues, preventing equipment damage and operational delays.
  • Wellbore Control and Stability: Maintaining wellbore stability, preventing influx, and ensuring wellbore integrity are crucial for safe and efficient CTD operations.

4.3 Optimization and Improvement:

  • Continuous Improvement Program: Implementing a continuous improvement program to analyze operational data, identify areas for improvement, and optimize CTD processes.
  • Leveraging Technological Advancements: Utilizing advanced technology, software, and tools to enhance drilling efficiency, safety, and wellbore performance.
  • Collaboration and Knowledge Sharing: Sharing best practices, lessons learned, and knowledge within the industry to improve CTD techniques and outcomes.

4.4 Conclusion:

Adhering to best practices in coiled tubing drilling is crucial for achieving optimal results, ensuring safety, and maximizing wellbore performance. Continuously improving processes and leveraging technology are essential for driving innovation and expanding the applications of CTD in the oil and gas industry.

Chapter 5: Case Studies in Coiled Tubing Drilling

This chapter presents compelling case studies highlighting the successful application of coiled tubing drilling (CTD) in various scenarios, showcasing its unique capabilities and advantages.

5.1 Case Study 1: Sidetracking for Reservoir Access:

  • Scenario: An existing well encountered a formation barrier, hindering access to a productive reservoir zone.
  • Solution: CTD was used to successfully sidetrack the wellbore, drilling a new trajectory to access the desired reservoir.
  • Results: Increased oil production, improved reservoir access, and reduced drilling time compared to traditional drilling methods.

5.2 Case Study 2: Re-entry and Well Stimulation:

  • Scenario: An abandoned well was successfully re-entered using CTD and subsequently stimulated using acidizing techniques.
  • Solution: CTD facilitated wellbore access and subsequent acidizing operations, leading to improved production rates.
  • Results: Resumed production from an abandoned well, enhanced reservoir productivity, and cost-effective revitalization of a previously unproductive asset.

5.3 Case Study 3: Horizontal Drilling in Tight Formations:

  • Scenario: CTD was employed to drill a horizontal well in a tight formation, where conventional drilling methods were impractical.
  • Solution: The flexibility of coiled tubing allowed for precise directional control and navigation through tight formations, maximizing reservoir contact.
  • Results: Increased oil production, improved reservoir drainage, and cost-effective exploration of tight reservoirs.

5.4 Case Study 4: Underbalanced Drilling for Enhanced Stimulation:

  • Scenario: CTD was utilized for underbalanced drilling in a low-permeability reservoir, optimizing reservoir stimulation and production.
  • Solution: The underbalanced drilling technique facilitated efficient stimulation, leading to enhanced production rates.
  • Results: Increased hydrocarbon recovery, improved reservoir productivity, and reduced drilling costs compared to conventional drilling.

5.5 Conclusion:

These case studies demonstrate the effectiveness of coiled tubing drilling in various scenarios, highlighting its advantages in sidetracking, well stimulation, horizontal drilling, and underbalanced drilling. CTD offers a flexible and versatile solution for optimizing well performance and maximizing hydrocarbon recovery, making it a valuable tool in the oil and gas industry.

Termes similaires
Forage et complétion de puitsGestion de l'intégrité des actifs
Les plus regardés
Categories

Comments

No Comments
POST COMMENT
captcha
Back