Rig Anchor Release
A remote, selective, quick disconnect of mooring lines for drilling rigs

The Rig Anchor Release (RAR) provides rapid selective release of mooring systems on drillships and semisubmersible drilling rigs. This capability can be used in a number of conditions, which can save time, equipment, and personnel. The RAR has been used in numerous offshore platform moorings for decades and is shown to be reliable and cost-effective. This is especially true in hostile environment where rig safey and mobility are critical and daily rates for drilling vessels are high.

  • Easy disconnect of DP/mooring capable and conventionally moored rigs
  • Selective quick disconnect of mooring lines
  • Allows rapid movement from location for ice, emergency, or severe storms
  • Reduce critical path time
  • Proven design technology
  • Simple and reliable
  • ABS certified

The next generation of Rig Anchor Release (RAR), the RAR Plus, builds on a 35-year history of proven acoustic release technology by adding several key features, including a mechanical backup release method. The new backup method ensures the ability to release the moorings in the unlikely event that the remote acoustic transmission fails to actuate the RAR. The mechanical backup release bypasses the acoustic, electronic, and hydraulic systems in the RAR Plus, and it can be actuated by either the rig itself or with a nearby support vessel.

The RAR Plus minimum break load (MBL) has been increased to accommodate modern R5 high-strength mooring lines. The increased repeatable release load limit allows for disconnection at extreme line tensions.

The RAR Plus internal components both directly measure and indirectly calculate line tensions in real time for display on board the rig in a user-friendly graphical user interface. This interface displays valuable data for use during mooring activities and for the duration of the drilling campaign. The data stream can also be input into 3D catenary monitoring systems, providing ultimate risk mitigation for mooring in congested fields. All data is saved in both the topside processing unit and locally within the RAR Plus memory for post-analytical purposes. The telemetry system is optional and can be easily removed for applications that do not require enhanced mitigation measures.

RAR Plus brochure


Mechanical Backup Sequence Using Rig Winches