Darren Santeler and Heather Byers, Vallourec USA Corp.
As drilling technology advances, operators are continuing to drill deeper and further than ever thought possible. Extended reach drilling and record breaking lateral lengths have brought new challenges to the onshore market, and tubular technology has had to evolve quickly to fill the gaps. Increased depths lead to higher formation pressure that must be managed. Longer strings and tighter formations require increased pressure containment. Longer horizontals becoming the norm with severe dog legs have made ultra-high torque a necessity. As the industry leading premium connection supplier, VAM® connects operators to engineered tubular solutions for the well designs of tomorrow.
Threaded and Coupled
VAM® 21 HT, the next generation threaded and coupled premium connection, features advanced sealing technology and maintains higher torque capability. VAM® 21 HT was the first connection to combine a gas tight metal-to-metal seal with 100% pipe body ratings. And with over 200 samples physically tested, it was the first connection qualified to the new ISO 13679 FDIS-2011 CAL IV protocol, and is fully API RP 5C5:2017 CAL-IV compliant within the full pipe body envelope. VAM® 21 HT is the highest performing and most reliable VAM® shouldered connection to date with excellent gas tight sealing under combined loads, extreme compression resistance (100%) and innovative VAM® Effect with the VAM® Stabilizer™ ensuring full sealability. The seal and shoulder functions are separated so that torque and compression act independently under extreme pressure requirements. This separation provides a much stiffer pin nose resulting in extra torque while maintaining full sealability throughout the life of the well. With the placement of the seal away from the pin nose, it is also protected from handling damage that conventional threaded and coupled connections suffer. VAM® 21 HT's unique multi grooving allows for dope pressure relief to ensure good clean make up graphs. It is easy to run, extremely reliable, and the superior choice for unconventional drilling.
For extended reach and horizontal drilling with extremely long laterals, ultra-high torque capability becomes a necessity. The higher torque is required to rotate the string through the curve and across the lateral portion into position. Unlike the vertical section, torque is used to combat gravity induced friction when in the lateral. When rotating the casing during cementing, higher torque is needed to overcome the friction and drag that the cement creates on the surface of the tubulars.
These ultra-high torques cannot be met with slight changes to existing connection designs. A whole new concept to the conventional threaded and coupled connection was required and led to the development of VAM® HTTC. In a standard shouldered connection, torque is limited by the surface contact area of the pin nose with the torque shoulder. In order to meet the ultra-high torque requirements, a change in the thread design was necessary. An innovative design with a variable width thread over the length of the connection creates a self-locking connection without a torque shoulder. This thread design allows for an increase in surface contact between the pin and box dispersing the stress concentration over a greater area. The advanced thread design combined with a metal to metal seal provides the highest torque rating of any threaded and coupled ISO qualified connection available with gas tightness. VAM® HTTC has been proven to provide excellent gas tight sealability with some of the highest torque ratings on the market and has been validated to API RP 5C5: 2017 CAL-IV. Furthermore, it has been validated to bend more than 42° per 100 ft with combined loading so it can pass through extreme dog legs in the most demanding well designs. VAM® HTTC is easy to run, with a low back-out rate and quick make up speed ensuring performance reliability.
When geology or government regulation requires an additional intermediate string, clearance becomes a major concern. To prevent a restriction of the production casing ID (and therefore fracture and production volume) or the need for a larger surface casing (increasing weight and overall cost), an integral connection becomes a necessity. Integral connections offer OD's that are the same as the pipe OD or a few percent over pipe OD, freeing up valuable space in the well design. For the next generation of wells, VAM® has designed a complete array of products to help customers hit their target well designs.
The first connection on the market designed with Shale Gas in mind actually uses that as its name – VAM® SG. Designed to withstand the high fatigue from horizontal rotation, pressure cycling from repeated fracture jobs and gas sealability after this loading, VAM® SG is the perfect candidate for wells requiring a semi-flush integral connection. The hooked thread form prevents jump out, the large contact mid wall shoulder provides high torque, and the run out thread enhances tension up to 91% in some sizes. To demonstrate the ability to be used in unconventional plays, VAM® tested this connection extensively using a dedicated testing protocol to copy the shale operational aspects provided through in-depth discussions with operators. Extreme tolerance samples go through high rotational fatigue, pressure cycling and internal gas testing before being released. This connection has proven successful in the most demanding wells in Haynesville and the Eagle Ford plays.
For extended reach horizontal wells that require slim well designs, high torque is still needed. To address that need, the VAM® EDGE SF was designed with the future in mind. Taking cues from the VAM® SG, it exhibits a mid-wall seal for full gas sealability with high fatigue life. A variable width dovetail thread drastically increases torque while preventing jump out at the same time. The result is a connection with double the torque of a conventional shouldered connection, and has been thoroughly tested across the product line.
A network of over 500 people is devoted to the design of innovative solutions in three R&D facilities around the globe. Our state of the art test labs prove VAM® ratings and reliability through physical testing across each product line. A full team of certified VAM® Field Service engineers is available 24 hours a day to help run VAM® connections, reduce NPT, and improve total cost of ownership.
Regardless of the projects operators have in mind, Vallourec is here to engineer the right tubular solution.