Evolution of Tubular Handling Brings Big Safety, Efficiency Gain

Safety and efficiency have long been the drivers in the evolution of tubular handling and running technology, from manual systems to highly mechanized and automated processes.

Safety and efficiency have long been the drivers in the evolution of tubular handling and running technology, from manual systems to highly mechanized and automated processes. As increasingly complex well construction demands have created new challenges and a heightened emphasis on well integrity, a more comprehensive approach to tubular management and running has emerged. Evolving beyond rotary table operations, today’s tubular running services also encompass an upstream focus on pipe preparation and makeup offline and a downstream emphasis that ensures high-integrity casing string installations to total depth (TD).

Tubular Management

Tubular management requires a comprehensive process that involves logistical planning, pipe storage, preparation, makeup, and wellsite planning to deliver pipe ready to run. A successfully executed offline process covering all of these factors yields greater consistency and reduces personnel and infrastructure requirements. Safety and efficiency gains are achievable by controlling how the pipe is handled, controlled, and run in onshore and offshore operations.

Offline pipe makeup for casing, tubing, and drillpipe is done at Weatherford with advanced oilfield bucking (Fig. 1) and torque-control makeup systems that employ the same technology used on rig systems for many years. The technology, which can be positioned at permanent facilities and on remote locations, is used to build ready-to-run double or triple stands of tubulars for delivery to the rig.

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Fig. 1—An advanced bucking unit is used to build ready-to-run double and triple stands of tubulars. The unit can be placed at permanent facilities or remote locations. Photo courtesy of Weatherford.

Delivery of rig-ready pipe to the wellsite limits the exposure of rig personnel to makeup and running operations and reduces pipe preparation cost and rig time. It also reduces openhole exposure time, which helps minimize wellbore stability issues and contributes to better casing running times.

Connection integrity control, beginning with planning and preparation, reduces the chance of failure and well repairs. As with rig-based systems, the offline technology makes or breaks connections using highly accurate torque measurements that are displayed and recorded.

The system ensures connection integrity and makeup parameters for API and premium thread tubing, casing, production riser, and drillpipe. Cementing accessories can also be made up and the system can be configured for subassembly of downhole equipment. Faster makeup speeds are enabled by rotational makeup and breakout technology that can be instantly reversed.

Detailed pipe connection data is collected off site or on the rig with unique identifiers barcoded on the pipe. Information recorded during offline makeup is merged with data from connections made up on the rig, including torque, length, drift, and tally. This synchronized data collection and automated traceability improves research, reduces nonproductive time, and lowers costs associated with connection integrity.

Efficiency and cost reductions are also achieved through streamlined tubulars selection, improved supply chain efficiency, and application of vendor and supplier management systems. For tubulars headed offshore, smooth logistics, packaging, and transportation depend on well-designed and -executed quayside operations.

US, Australian Case Studies

Significant well construction safety and efficiency gains have been achieved in using this tubular management process, whether working from permanent facilities in areas with mature infrastructure or from mobile systems in remote locations.

For example, in the United States Gulf of Mexico (GOM), an offline tubular makeup system was used to build double stands of 14×13⅝-in. casing, which was delivered rig-ready to the wellsite. Operations were based at a newly built company tubular preparation and automated pipe makeup facility in Port Fourchon, Louisiana.

The 17,000-ft string was run in 26 hours compared with a previous well in which a similar 14,000-ft string run in single joints required 41 hours of semisubmersible rig time.

Across multiple GOM applications, the tubing management process has improved handling and run times by as much as 78% (Fig. 2) and resulted in substantial commensurate cost savings over 28 casing string installations.

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Fig. 2—Tubular handling rates and process efficiency improvements are shown for 28 casing string installations in the US Gulf of Mexico that used a tubular management process incorporating offline pipe makeup. Graph courtesy of Weatherford.

Similar results were achieved offshore northwest Australia, where double stands of casing and tubing were built offline and delivered to a semisubmersible rig. A bucking unit with torque turn process-control systems was placed at the operator’s onshore support base to make up double stands of 9⅝-in., 7-in., and 4½-in. tubulars.

Running double instead of single joints improved efficiency by 30% to save an average of 4 hours per tubing running operation and 32 hours in total tubing running. Offsite pipe preparation saved additional rig time. The cost savings achieved throughout the tubular management process were significant.

Evolution of Tubular Handling, Running

Tubular management capabilities reflect substantial advances in tubular running and handling technology achieved over the past 2 decades. These advances have helped to move personnel out of harm’s way and significantly improve rig efficiency. Key innovations have included topdrive technology, pipe racking systems, and increased rig mechanization.

In the 1980s, semiautomated and mechanized rig applications began to replace conventional tools such as manual tongs, hand slips, and elevators, as safety engineers sought to remove hazards from the system. This advance primarily involved modifying existing hardware for modularity and, preferably, remote control.

The mechanization process contrasted with traditional automation concepts that typically required expensive and cost-prohibitive redesign of rig components. Instead, rig mechanization provided a much more cost-effective approach that achieved safety goals by distancing rig personnel from the hazardous location.

Replacement of these semiautomated and mechanized packages began with the introduction of topdrive casing running systems and the ability to control all derrick and drill floor operations remotely. The use of fully automated pipe handling and makeup equipment eliminated power tongs and other casing running equipment on the rig floor, along with the personnel required to run them.

The benefit of these automated casing running and tubular handling systems was leveraged by many other innovations. Casing circulation and fill-up tools along with flush-mounted casing slips eliminated backup tongs and greatly reduced working heights. Improvements to automated tong positioning systems eliminated the need for manual handling of larger power tongs. Modular systems provided interchangeable mechanized power tongs for casing, tubing, and drillpipe. Multitask versatility combined the capability to perform casing connection makeup, torque monitoring, casing fill-up and circulation, rotation and casing reaming and drilling, and elevator functions.

The focus on risk reduction and efficiency gains resulted in the removal of workers from the drill floor casing running operations and the elimination of some functions. For instance, automated casing stabbing systems removed the individual in the derrick, which has led to a major reduction in casing stabbing board incidents over the past 14 years.

For example, the use of automatic side doors has eliminated the risk of hand, finger, and back injuries from manual operations, particularly with larger-diameter pipe. Power tong positioning systems have also reduced manual handling in moving large, heavy power equipment around drill floors, which poses particular risk in bad weather by contributing to rig heave and causing dangerous pipe swaying.

These advanced tubular handling systems have played a significant role in improving safety. Industry figures in the GOM for casing and pipe handing incidents show a decline from a high of almost 14% in 1997 to 0.09% today. Similar figures have also been reported in the North Sea and Australian operations.

Below the Rotary

Technology advances that have revolutionized the rig floor have also had a significant benefit downhole. The right choice of running equipment and its integration into the rig systems during front-end engineering and development is critical to downhole and rig performance.

Improvement in the downhole dimension of casing running resulted from the development of topdrive systems that simultaneously rotate, circulate, and push casing strings. These systems significantly improved traditional tubular running operations. But they also required downhole engineering measures, as opposed to reliance on traditional rig-floor competencies. Rotating and pushing casing introduced torque and drag, cyclic fatigue, bending, and compressive loading, all of which require complex analyses.

Integration of the new capabilities with the existing process required multidiscipline expertise and an understanding that exceeded traditional tubing running operations, which generally ended at the rig floor. The expanded competency, combined with enabling technologies, widened the perspective from the traditional tubular running process to a TD-enabling process more closely aligned with the operators’ overall wellbore objectives.

Today, new levels of safety and efficiency are being achieved by extending the focus from making connections at the rotary to bringing high-integrity casing strings with the planned diameter to TD and securing the wellbore over the life of the well.

Evolution of Performance

The evolution of tubular handling and running technology from manual systems to highly mechanized and automated processes has resulted in remarkable improvements in safety and efficiency. While new challenges are presented by increasingly complex operational and economic demands, advances in technology and methods are being combined in a comprehensive approach to tubular handling and running that is achieving even greater levels of performance.