Real-Time Fiber-Optic Integrated System with Retrievable Packer Enables Single-Trip Dual-Zone Evaluation: Case Study, Eastern Foothills, Colombia

Day 1 Tue, March 26, 2019

et al. 2019

New downhole coiled tubing (CT) technology was used to facilitate the success of a challenging fishing intervention and to verify the reliability and accuracy of CT operations/simulation software. The technology supplies the newly designed bottomhole assembly (BHA) with continuous power from, and fiber-optic communications with, surface equipment, enabling accurate, real-time monitoring of measurements of bottomhole conditions. Uncertainty exists in operations using CT regarding whether the planned axial force is transmitted from the surface through the pipe to the BHA and whether the BHA is functioning according to plan. During fishing operations, unless the BHA applies a minimum amount of force (compression and/or tension) to the fishing neck, the particular intervention run will be unsuccessful. The BHA then needs to be returned to the surface without recovering the fish. This paper presents a case study of a well located in the foothills of Colombia in which a perforating gun became stuck following an operational issue. This situation resulted in an oil production reduction of 30%. Several fishing attempts were performed using conventional CT to recover the stuck perforating gun and to restore production to its previous level. The initial lack of real-time BHA data and the inherent nature of CT elongation and buckling led the operator to believe that the fish was being recovered to the surface; several runs were performed with unsuccessful results. A CT string, equipped with fiber-optic communications and a continuous power supply to the BHA, confirmed that the perceived movement of the fish was not real and that the BHA selected was not generating nor transferring the expected force to the fish. The force transmitted by the pipe and the upward/downward impact force generated by the jar were measured in real time and determined to be consistent with simulated forces; the BHA configuration used for the operation was then redesigned. The new design led to the successful recovery of the fish and the return of well production to its initial level. The real-time data measured during the fishing operation favorably compared to the simulated forces predicted during job design and execution. The accuracy and reliability demonstrated by the CT simulation software in use enabled the operator to gain confidence in all simulations performed with the software for future CT operations. This case study is the first known instance in which CT was used in conjunction with downhole tools that were supplied with continuous power to sensors to enable measurement of parameters, including force, pressure, temperature, torque, inclination, phasing, acceleration, gamma ray, and casing collar locator (CCL). This technology was supported by reliable software capable of simulating downhole conditions with precision and accuracy.

Successful Coiled Tubing Fishing Operation Uses Hybrid Cable Connected Tools to Evaluate/Validate Downhole Data in Real-Time: A Case Study in the Eastern Foothills of Colombia

Vera

Torres

Day 1 Tue, March 26, 2019

et al. 2019

Real-Time Fiber-Optic Integrated System Allows Precision in a Surgical Sand Plug Settlement of a Temporary Well Isolation Operation

Vera

Torres

Day 2 Wed, March 27, 2019

et al. 2019

Pumping sand through coiled tubing (CT) with real-time capabilities is not a common practice because of potential risks associated with cable integrity. A successful sand plug settling procedure supported by a real-time fiber-optic integrated system under critical well conditions was of high importance during a recompletion intervention, allowing optimization of time and costs. Multiple methods are used to isolate a well during recompletion activities; nevertheless, a cost-effective method to divert involves setting sand plugs with CT and a real-time fiber-optic integrated system, which is essential to achieving precise settlement of the sand, not just for depth but also for volume of sand pumped. Without this complete system, the operator would need to make extra runs for correlations with electric line (e-line) or CT units, which increases both cost and operational time. A real-time fiber-optic integrated system allows adjustment to the sand plug stages in real time to help ensure top of sand (TS) necessary to isolate the producer formation and keep out the wireline entry guide without additional runs and increased costs. A casing collar locator (CCL) tool permitted the correlation depth to be measured in each tag, ensuring knowledge of where the sand was placed and helping prevent incorrect depths resulting from uncontrollable factors, such as elongation. More than 6,500 lbm of sand was pumped through CT using a real-time fiber-optic integrated system without losing communication with the downhole tools and without affecting cable integrity, which could lead to bird nesting the cable because of high friction and excessive slack inside the pipe. This real-time fiber-optic integrated system begins a new generation of sand plug operations by helping prevent additional runs or having other units correlate, particularly if a recompletion activity is programmed and space accommodation is a challenge because of the workover unit.

Deepwater Pipeline Pre-Commissioning Operation Using Large Diameter Coiled Tubing Instead of Standard Downline: State of the Art of This Technology

Rodrigues

Day 1 Tue, March 26, 2019

Frotte

2019

Deepwater fields present challenges to the pre-commissioning of the pipelines responsible for transporting oil and gas. Hydrostatic pressure exerted by long water columns to the downline system must be addressed and overcome because it can collapse the downhole equipment that had previously been used only in shallow waters. With the development of deepwater fields, coiled tubing (CT) provides several advantages over regular downlines. Considering that the pipelines are longer than 200 km and larger than 20 in. diameter, months of continuous work are necessary during their pre-commissioning; consequently, higher flow rates are required to reduce time and costs. Large-bore CT as downline has proven to be a cost-effective and reliable means to access deepwater pipeline pre-commissioning. With reduced layout and costs, as compared to regular downline systems, CT can provide the only economically feasible solution for some scenarios. To extend CT life without compromising its integrity and the operation, on-site pipe management and high cycle fatigue studies were conducted. A multi-skilled crew also helped to reduce personnel on board for a small vessel application without reducing health, safety, and environment (HSE)/service quality (SQ) levels. Customized and reduced equipment layout was implemented to address deck load and space restrictions. The use of a regular downline dramatically affects costs because several external layers must be added to provide suitable collapse pressure resistance, increasing its diameter and requiring a larger storage reel in accordance with minimum bending radius (MBR) to avoid damage to the downline, compromising deck layout. Complex manufacturing increases procurement costs and timing, and makes on-site repair capabilities impossible. However, 3.5 in. CT considerably reduced the final operational time, reducing friction pressure losses while maintaining a feasible layout. Improvements made on rig-up and operational procedures, as compared to previous similar project experience, enhanced technology advantages and reduced the deployment and recovery time needed. Because of vessel limitations with rough weather conditions on this project, the CT eventually had to be recovered to the surface. Consequently, these improvements reduced rigging time and safely extended the operational window, enabling multiple deployments, even within shorter intervals of fair weather. An optimized deck layout for CT and monoethylene glycol (MEG) collection spreads was necessary for small vessel use; it reduced customer costs, considering that a much larger vessel was simultaneously operating on the other pipeline end for the largest high-pressure dewatering spread ever installed on a vessel for a pre-commissioning operation. The CT control cabin was placed perpendicularly to the reel; consequently, a closed-circuit TV system was mounted behind the reel to allow pipe spooling. Brazil's largest and deepest pre-commissioning operation was performed safely with service quality excellence, increasing efficiency levels of the industry within this scope of work. Several lessons learned have been assessed for further improvements.