Field bus network on deep sea oil exploration platform

Oil exploration platforms can tap into deposits under the sea down to 3,500 m deep. In shallow waters such as the Gulf of Mexico the platforms are firmly anchored to the sea bed. Oil exploration platforms suitable for the high seas must keep their position above the bore hole with engine power in spite of the wind and currents. Their position is recorded by satellite with GPS and by sonar buoys on the sea bed. Their position is maintained by powerful electromotors on the four corners of the platform.

These can revolve through 360 degrees. The dynamic position maintenance control system and the associated field bus network must meet high real time and reliability requirements. Converteam opted for the FIP field bus protocol for the Transocean Sedco Forex express class platforms and networked the control components with Hirschmann™‘s fiber optic cable repeaters.

Project parameters

• Positioning accuracy better than 5 m
• Maximum ocean current 3.5 knots
• Maximum wind speed 60 knots
• Maximum wave height 9 m
• Installed engine rating 4 * 7MW
• Maximum water depth 3500 m

Requirements

• Real time enabled bus system
• Error monitoring and alarm indication
• No single point of failure
• Error tolerant control system

Solution

• Complete optical networking
• WorldFIP field bus system
• Four hierarchically structured field bus rings
• Dual design, multiple meshed ring in dynamic positioning system
• Constant status monitoring in dual monitor systems
• 40 OZD FIP G3 T LWL repeaters per platform
• LWL cable with multimode 62.5 / 125 μm fibers
• Maximum cable length 300 m

Why Hirschmann™?

• WorldFIP field bus has very high real time capability
• Hirschmann™ LWL repeater‘s ring capability
• Very fast switch time should the ring fail
• Use of error contact in the platform‘s SCADA system
• Quality standard confirmed by Survey