Page 30: of Offshore Engineer Magazine (Jul/Aug 2013)

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Emergency Release Connectors

Drilling designed for high bending moment

View of face-to-face interface instead of the traditional male to ensuring reliable release.

female confguration, the XR connec- tor is capable of releasing safely with the Ocean Odyssey, are 100% maximum bending moment far-reaching. applied.

Furthermore, there is no It has no maximum disconnect angle offcial record of the num- and thus will not get stuck or fail to ber of times that connectors release when it is required to act.

fail to release on demand Most importantly, the XR connector due to excessive rig offset. continues to provide options beyond though unoffcial fgures normal operating limits and remains suggest that such events operational even after a complete riser could be occurring 15 to 20 failure. times globally each year. This is especially problematic for

Additionally, when exist- foating vessels, on which an error in ing ERCs are disconnected with an off- the dynamic positioning system or

By Drummond Lawson, managing set, but within their design limitations, loss of position due to particularly bad director of Subsea Technologies Ltd.

they still tend to become damaged by weather can quickly precipitate a cri- n the wake of the Macondo incident, the disconnect process, leading to rig sis, causing vessel and environmental the drilling industry has focused on downtime and repair costs. It is there- damage and, potentially, casualties. making improvements to offshore fore imperative that these issues are Conventional connectors have a

I safety and developing methods to addressed by the industry. geometry-limited maximum disconnect recover from similar incidents. The resulting emergency disconnect angle to prevent them from “locking

However, emergency release connec- package (EDP), the XR connector, broke up.” tor (ERC) technologies, which might with several design conventions asso- This means that, to operate within prevent or signifcantly reduce the ciated with existing connectors and the limited angle, the vessel is limited impact of such disasters, are yet to ben- solves its essential problems. in the distance it can move from its eft from this innovative process. Using a face-to-face engagement, central position, giving the crew little

While incremental developments reaction time to identify a loss in posi- to existing connectors might provide tioning and respond accordingly. some benefts, their design contains a As the XR connector uses a face-to- fundamental faw. face engagement, it does not

Based on the traditional male-to- require axial movement to female engagement, existing ERCs have separate the male from the operational limits, because of their female. geometry, and the connector may to Instead, the female face fail to separate if unlocked with will simply roll away a high bending moment from the male face, if applied. triggered to release

Failure to disconnect with full bending from the well head in load applied. As this situation can lead a result, it does to a major accident. The not even require consequences of such the topside riser incidents, as seen in the tensioning system aftermath of Macondo to be operational and other disasters, includ- in order to disconnect ing the 1988 blow-out on successfully.

When an operator ana-

Section view of XR Connector.

lyzes the bending capacity

OE | July 2013 oedigital.com 32 032_OE_0713_DC2-XRConnector.indd 32 6/25/13 1:00 AM