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A-frame. Operators are also concerned about spare parts supply support, the acquisition of missing parts of the spare systems to provide a complete spare system, tool ratings for HPHT sce- narios, and the contract model that should be addressed, FMC’s

Fonseca says. Despites this, interest in the system seems to be on the rise.

Much like the need for the development of the second gen- eration DPRIS, as the industry heads to ultra-deepwater, such as in the Gulf of Mexico (GOM), suppliers must be prepared for the demand of 15,000-20,000psi-rated DPRIS. “The GOM looks like it’s about to turn the corner and start adopting the technology in a more widespread basis. [It] will

Finding an probably be the most active areas for the technology,” Jellison says. “It’s starting to pick up fairly signifcantly. There’s lots of interest in it. We’ve had interest from several of the major operators of deepwater within the last year.” alternative

The challenge for DPRIS technology is the high pressure involved for applications in the GOM, and also in the types of tools commonly used. The larger tool types, such as plugs, are common in the GOM but will not ft in current DPRIS confgura- tions. So that’s where the next generation is heading — toward

Animated picture of the ocean foor properties of Vallourec.

This frst generation drill pipe riser, VAM DPR SR, included larger pipe and tool joint ID’s.

Image from Vallourec.

a Tefon ring on the shoulder that provided gas-tightness up to “In the past, NOV has been limited to an OD of 6 5/8in, which 5000psi working pressure. First used offshore Brazil, the system limits the size of the tools that can be run inside the pipe, but Photo from

DPR-2500m 5K System Stack-up at P-XXII rig (Brazil).

FMC Technologies.

was later brought to offshore Angola, West Africa, in 1999, there’s a strong need and desire for larger sizes. As a result, we’ve where Total deployed the system at the Girassol project, via been working on an intervention system with a larger OD,” could be an issue, the DPRIS can be delivered with resistance to FMC Kongsberg. At Girassol, 33 wells were drilled and DPRIS Jellison says. Also, due to torsional limits during makeup, there

SSC, as well as other forms of corrosion-assisted cracking. The was deployed 66 times for Xmas tree and tubing hanger instal- will be a new optimized design for the connection.

resistance is incorporated as part of the structure of the steel lation. During its 14 years of deployment in Angola, the system Vallourec is addressing the need to widen the ID by using a itself. “We use special chemical compositions of the steel and has been run more than 180 times. The systems are inspected proprietary grade of steel and changing the connection design. special processing,” says Michael Jellison, senior vice president every 3000 hours of use time. And, for the frst 12 years of “We have our high-strength materials that are called VM 150 of engineering, Grant Prideco, part of National Oilwell Varco deployment, only 25 connections needed repair, says Vincent and VM 165. They have 150,000psi and 165,000psi, respec- (NOV) Wellbore Technologies. Flores, Vallourec global product line manager. tively, as the minimum yield strength. The interest of those

Simply put, the drill pipe intervention system is a tube that is However, despite the success of the frst generation DPRIS, it grades is that you can increase the performance, via tension upset on the ends (a forging technique that thickens the wall at has its limitations, and with industry moving to deeper felds, and pressure ratings, without having to increase the weight of the tool joint) with highly specialized male and female connec- the system needed to adapt to the changing environment. Thus, the wall thickness,” Flores says. For the new connection, the tions. The major difference between normal drill pipe and drill 2006 saw the launch of the second generation DPRIS, VAM DPR design will use new threads and geometry. As a result, the OD pipe intervention system is the incorporation of a high-pres- HP, which could be used at greater depths than the frst genera- of the new product will remain closer to the previous genera- sure, gas-tight seal. “In general, DPRIS gives you access to the tion. VAM DPR HP is rated for 10,000psi working pressure. tions, while the ID is enlarged.

Successful deployments in Brazil and West Africa have led well. It allows you to connect to the well and perform various However, the Tefon ring was replaced with a metal-to-metal to signifcant improvements and growing confdence in DPRIS types of completions or intervention riser functions. It’s really a radial seal design. In 2010, this second generation system was technology. With a new market burgeoning in the GOM, DPRIS means to get access to the well or to install critical components frst deployed off Nigeria, West Africa, at another Total-operated manufactures could see global interest in this technology rise.  on top of the well,” Jellison says. project, USAN, mainly for Xmas tree and

Within one system, users have simultaneous access to a tubing hanger installation, as well as some

VAM DPR SR Connection – properties of Vallourec. completions and intervention system. DPRIS is applicable for well testing and well clean ups. “From 2010

Photo from Vallourec.

use with Xmas trees with fragile studs, Xmas tree and tubing to 2015, there were a total of 75 connections, hanger installation, retrieval, testing, hydrate disassociation, which needed some repair, after hundreds of 6 5/8” Grant Prideco Drill Pipe Intervention Riser with XT-M

Connections. Photo from NOV.

downhole valves maintenance, well test, sand removal, and runs performed by the system. Each DPRIS more, says Luiz Fonseca, service manager for subsea services at can actually be rethreaded several times,

FMC Technologies. thanks to its extended tong lengths. Hence, “Furthermore, the systems are able to operate as early produc- it allows an enhanced lifespan compared to tion risers (EPR), providing a system that can perform long-term conventional riser systems,” Flores says. The well testing. In the past, this system represented the sole produc- system is still currently in use at USAN and tion system of one basin, working at a foating, drilling, produc- has been deployed in Brazil as well.

tion, storage and offoading (FDPSO) vessel,” Fonseca says. However, every technology has limitations

With more than 50 systems operating around the world, and room for improvement. DPRIS is limited

DPRIS popularity is gaining momentum. by CO in high-pressure, high-temperature 2

The frst system was developed in the mid-1990s to fulfll (HPHT) conditions, moonpool dimensions, a request by Petrobras for a rugged system that could hand power supply current and nearby deck space numerous makeups and breakouts. The results was the adapta- required to lay down the hose reel that must tion of drill pipes for gas-tightness. be lined up with the moonpool and derrick oedigital.com August 2015 | OE 31 030_OE0815_Feat2_Jerry.indd 31 7/21/15 3:54 PM