Tuesday, 15 September 2015

Plexus Holdings taps subsea market

by Elaine Reynolds

The launch of Plexus Holdings' Python Subsea Wellhead at Offshore Europe 2015 is a major step for the company, allowing it to access a previously untapped market with its innovative POS-GRIP technology. 

POS-GRIP was invented and developed by Plexus founder-CEO Ben van Bilderbeek and is a patented method of friction grip engineering which the company has used to redesign wellhead systems.

The wellhead market has been dominated by large US companies such as Cameron (currently expected to be acquired by Schlumberger for around $14.8bn) and FMC Technologies. Yet Plexus currently has almost 100% of the UKCS exploration jack-up drilling wellhead market, and has also been particularly successful in HP/HT exploration applications where technical demands are greater. Until the introduction of Python however, the company did not provide a subsea system, so this should allow the company access to a much larger market. Interest in the system can be seen in the calibre of companies that have supported the joint industry project to develop Python, including BG, Shell, Wintershall, Maersk, TOTAL, Tullow Oil, ENI, Senergy and Oil State Industries. The Python Subsea Wellhead is planned to be run in a trial well during 2016.

POS-GRIP system

POS-GRIP open                                                                                         POS-GRIP closed

The system uses hydraulic devices fitted to the outside of the wellhead which, when energised, deflects the outer wellhead body onto the inner casing hanger or tubing hanger, locking them in place. POS-GRIP is a significantly more streamlined design than seen in traditional wellhead technology and offers improvements in reliability, safety and cost.  In particular:

  • The system virtually eliminates the movement between sealing parts that causes seal deterioration and failure. 
  • All well operations can be carried out through the Blowout preventor (BOP). This saves a significant amount of rig time and improves safety as the BOP is in place at all times.
  • Hangers are sealed and locked as soon as cementing is completed, preventing hanger movement under pressure (as occurred during the Deepwater Horizon incident).