Subsea control systems play an important role in acquiring, managing and providing the information that enables subsea production systems performance to be enhanced. Reliable operation, combined with accurate control and monitoring of subsea installations is essential to ensure the highest production availability, while providing safe and environmentally friendly field operations.
Hydro Group provide diverse interconnectivity solutions for:
• Subsea control modules (SCM) – Pods
• Subsea electronic modules (SEM)
• Acoustic monitoring system (AMS)
• Various instrumentation system
A dynamic flow line control cable or umbilical is designed to hang in a centenary form between a fixed structure or wellhead platform (WHP) and a floating structure (FPSO). This type of umbilical is normally low in weight with either contra helical armour or Aramid fibre to endure axial loading. This dynamic flowing cable would normally incorporate power conductors, instrumental and fibre optics (fiber optic) for high data transmission.
Throughout the entire length of the control cable the armour or aramid fibres functions as a load bearing member. The strength members are utilised to secure the umbilical to each installation via a hang off device using flanges, fixing nuts and bolts, bend stiffeners or bend restrictors are installed to protect the cable at vulnerable interfaces. All jacket material is low smoke halogen free thermoset oil resistant compound. The design life of the cable will be at least 10 years and stable when hanging in water.
Fibre Optics (Fiber Optics) are constructed with tight buffered, individual fibre reinforced with aramid yarn. The outer jacket is low smoke halogen-free. Termination of the dynamic cable is via splitter junction boxes with suitable connectors or hard wired for locating in a Zone 1, Gas Group 114, Temp Class T3.
The electrical cable jumper provides power and signal distribution to components of the subsea production system. Signals may be transmitted via combined signal or power cable or separate fibre optic signal and power cable. The electrical jumper may consists of an over sheathed, armour cable comprising of two twisted screened pairs (TSP’s) and a aluminised mylar tape screen, terminated to two high integrity electrical connectors. The pressure compensated electrical inserts within the electrical connectors allow the electrical jumper to be mated subsea.
The acoustic monitoring system will transfer data from a subsea monitoring transponder to the operator station at the on board system. The data to be transferred may comprise any data that the SMT receives on a serial line or on an analogue input. Subsea or down-hole sensor time tagged data from gyrocompasses, inclinometers, temperature sensors, pressure sensor and other devices may be transferred to the on board system without the use of cable. The cables are interfaced via cables to the SMT and the interface normally ends in an underwater connector or in an open-ended cable for moulding onto the customer’s equipment.