Seal of Approval - European Oil and Gas

Published in European Oil and Gas
November 2013

Last year’s blowout in the Gulf of Mexico served as a reminder of the inherent dangers involved in modern oil and gas exploration. E&P is increasingly moving to remote areas, deeper waters, and to formations, where higher pressures and temperatures (HP/ HT) can mean that well control safety becomes even more essential.

While it is not yet possible to exactly determine why the BOP failed to close, the incident has clearly highlighted the issue of how casing hangers are installed in subsea wells.

Close analysis of drilling operations has uncovered the habit of installing subsea casing hangers in the well without being locked down in the wellhead body. Many experts have related the failure to lock down the Macondo well casing hangers to the extended period which was required to kill the well, and it is believed that in direct response to these concerns the US Department of the Interior decreed that in the future all subsea casing hangars must be locked down into the wellhead system as soon as cementing operations are completed.

While these new requirements will represent a challenge for the wellhead companies, who over the past 40 years have failed to provide dependable hangar lock-down solutions, for one business – PLEXUS Holdings Plc – the new rules provided the opportunity to invest further in and develop its unique and groundbreaking POS-GRIP® friction-grip wellhead technology.

Although initially applied in wellhead designs for jack-up exploration drilling projects POS-GRIP technology holds a number of unique and technical advantages that set it apart from anything else on the market. These features are best illustrated in situations where surface wellheads require some adjustability for the casing hangars, and where metal-to-metal sealing for HP/HT conditions is essential.

In all its applications POS-GRIP technology features instant hangar lockdown and metal-to-metal sealing capability, which renders this patented technology ideal to meet the new standards now required for wellheads.

At the request of a number of international operators PLEXUS has begun to study the possibility of developing POS-GRIP solutions for subsea applications. As part of this process the company has conducted a range of in-depth investigations to ascertain the extent to which a joint industry project (‘JIP’) to apply friction-grip technology in subsea applications would be supported.

PLEXUS CEO Ben van Bilderbeek, an accomplished and successful engineer and entrepreneur who has over 30 years’ experience in the industry, and the man responsible for inventing and developing POS-GRIP explains: “Because conventional lock down solutions were found to be insufficient, a major US independent operator (IOC) requested that we consider applying friction-grip subsea prompting our investigations.

“We used the various discussions with a range of international operators to learn whether there were additional areas of concern in respect of the capability of existing technology,” he continues. “Our findings reveal that in addition to the requirement of instant hangar lock down, the ability of conventional technologies to maintain seal integrity throughout and beyond the life of the well is also in question.”

As Mr. van Bilderbeek explains, operators were able to voice a number of concerns that helped PLEXUS understand better as to how its technology is ideally suited to address a range of key concerns and issues raised both by the industry itself, and regulators, particularly BOEMRE in the US: “We also found that operators wanted true metal-to-metal seals.

“We will tailor our technology to be uniquely capable of dealing with hot and high pressure wells by including the ability to tension casing strings remotely.”


Read the Full Article Here