Sandvik Materials Technology has launched ClikLoc, a new workover/completions riser connector that offers make-up/break-up times measured in seconds, effective metal-to-metal sealing, and good safety characteristics.
ClikLoc connectors are incorporated in a coiled tubing stack-up riser package in use on ConocoPhillips’ Ekofisk 2/4-X platform.
ClikLoc has undergone successful prototype testing by several operators on the Norwegian continental shelf, according to business development manager Ivar Hognestad.
- A coiled tubing stack-up riser package incorporating ClikLoc connectors has been used since Aug. 2005 by BJ Services, the coiled tubing services contractor on ConocoPhillips’ Ekofisk field in the Norwegian North Sea. BJ Services has reported a typical saving of 36 hours for rig-up/rig-down time, meaning less production time lost.
- A ClikLoc connector was delivered to Marathon for use in a drillstem testing landing string, where it provides the last connection below the surface flow-tree. In addition to substantial time savings, ClikLoc makes the operation simpler as there is no need to rotate the surface flow-tree when making the connection.
- A ClikLoc riser joint was supplied to Schlumberger as part of the riser deployed through the heave compensator for well intervention on Statoil’sHeidrun TLP.
ClikLoc was designed from scratch to meet the new ISO 13628-7 standard for workover/completion risers, says Hognestad. Some changes were made to improve the design based on the experience acquired from the prototypes. Now it has been launched as a commercial product for topside applications.
Simple procedure
ClikLoc is a self-centering stab-in connector with a vibration-safe locking device. Operation is simple and foolproof. Once the two sections have been stabbed together, the joint is secured by turning the sleeve through 45° and then turning the vibration locking sleeve. If the connection has not been correctly made, locking is impossible. The procedure can be carried out by the regular rig crew without the need for any specialist assistance.
A dual-bore workover/completion riser with a ClikLoc connector.
The operation is also extremely rapid, taking a mere 10-15 seconds per connection. That compares with up to one hour for conventional connectors. For a 1,500-m (4,921-ft) riser, the running time is reduced from 30 hours for a conventional riser to five to 10 hours for ClikLoc, Hognestad says. Similar time savings accrue when the riser is being dismantled.
The operation is also safer, as no rig tongs or other tools are required for make-up and break-up. In addition, there are no loose parts, so the risk of dropped objects is eliminated.
ClikLoc has a metal-to-metal seal, as required by offshore regulations. There is a lack of suitable products with metal-to-metal seals on the market, with the result that the regulatory authorities sometimes make exemptions to allow the use of products with elastomer seals, despite concerns about the integrity of such seals in hazardous conditions. ClikLoc helps fill the gap.
The seal is made from a titanium alloy. This material was selected after a lengthy R&D program into the use of titanium as a high-pressure sealing material carried out by Sandvik Materials Technology. A patent is pending for the sealing technology. To secure the tightness of the metal seal, only one to two tons of tension is needed, compared with 35-40 tons (31.75-36.3 metric tons) for a flanged connection.
The body of the connectors is made of SAF 2507 (UNS 32750) stainless steel. This improves the product’s fatigue life by around 20% compared with carbon steel and ensures that it meets NACE standards for sour service, says Hognestad.
Sandvik plans to seek type approval for use of the connector in subsea workover/completion applications. A contract should be placed this fall for the physical testing, which will be verified by an independent third-party classification society.
The connector currently is qualified for operational pressures of up to 10,000 psi, but Sandvik plans to increase the rating to 15,000 psi. It is qualified for temperature ranges from -18° to 121° C (0.4°-250° F), but the ceiling is to be raised to even higher temperatures. This will make it suitable for extreme high-pressure/high-temperature well applications.
The idea for the product was initiated by the Norwegian company Gram Sealing Technology. Sandvik Materials Technology purchased the idea and all rights to the product in 2004 and has since used its own R&D resources to develop it into a commercial product. The company’s Stavanger office is responsible for further development of ClikLoc.
Bringing this product to the market represents a strategic move on the part of Sandvik Materials Technology, from supplying raw materials and half-finished products towards becoming a systems supplier, Hognestad adds.
For more information, contact Ivar Hognestad, Sandvik Gram. Tel +47 5169 4060, fax +47 5169 4099,[email protected], www.smt.sandvik.com/oilgas.
