The Installation and Workover Control System (IWOCS) controls and monitors the deployment, the operation and the retrieval of subsea production equipment.

Main features of the IWOCS are:

• Monitors and controls deployment and retrieval of Tubing Hangers, Landing Strings and Xmas Trees
• Provides facilities for downhole operations, well testing and production testing
• Workover equipment is standardized and can be adapted to field and customer requirements
• Direct- and electro hydraulic systems are available

The direct hydraulic system operates the subsea and downhole hydraulic functions through dedicated hydraulic lines in the workover umbilical. It comprises a workover control container, local control panels on the rig and a reel which enables the control umbilical to hook up to the subsea equipment. This technology is well suited from shallow to medium water depths, and has been supplied as part of the majority of subsea systems provided by FMC.

The electro hydraulic system operates the hydraulic functions mainly through a Riser Control Module (RCM) inside the marine riser. Small diameter control umbilicals and very short response time are achieved using the electro hydraulic system. This is compatible with deep water operations as it is very successfully demonstrated through the Total Girassol system.