The Inter-M Pulse long-term mooring connector, developed by InterMoor in conjunction with sister company Pulse Structural Monitoring, was recently put through its paces in a North Sea field trial. Alan Duncan, MD of InterMoor UK, reported during OTC that the system has the capability to monitor and track the in situ tension of each mooring line and transmit tension data acoustically to a topside control room.
With the introduction of various sensors, the Inter-M Pulse can also detail inclination of the mooring line. Additional features include full history of the mooring line, acoustic data transmission, on-demand data upload and a traffic light alarm system.
To ensure the technology of the Inter-M Pulse, a 76mm, 800t minimum break load unit was installed over the stern roller of an AHV for the Ocean Nomad semisubmersible at Everest 22/10a in the North Sea last winter for a six-month drilling campaign. The unit deployed was designed for use on all offshore units. The field trial mooring system consisted of a combination chain and fibre makeup with the unit installation located at the fibre and shackle connection.
Typical sea states of around 12m were encountered during the trial but at all times the Inter-M Pulse was able to send accurate line tensions and inclination readings to the control room, said Duncan. After a successful installation, the unit was immediately operational and feeding line tensions and inclination readings to the surface. The data was sent back to the topside system via the acoustic data link once a minute for several hours a day. The readings have since been verified and documented.
‘In addition to its valuable use in permanent and drilling moorings worldwide, the Inter-M Pulse could prove crucial for operators as US regulations demand that rig managers and production unit operators report on the status of their mooring systems after a hurricane,’ said Duncan. ‘This technology allows full calibration on mooring chains without losing valuable rig time.’