Subsea Well Control Systems

Weatherford’s electro-hydraulic multiplex subsea control system is a modular design concept incorporating well established technology and qualified components to minimize both capital and operating expenditure costs. It is field proven with all major tree manufacturers and is adaptable to specific needs. The control system is used in subsea shallow and deep well locations around the world. The integrated system provides the requisite monitoring, control and shutdown functions by means of multiplexed electro-hydraulic control.

An integrated system provides the requisite monitoring, control and shutdown functions by means of multiplexed electro-hydraulic control. Network connectivity uses communications on power lines between a surface master control station (MCS) and subsea control module (SCM) via a composite services umbilical and appropriate subsea distribution unit(s).

The subsea electronics module (SEM) is enclosed in a 1-atmosphere dry nitrogen purged housing located within the main SCM housing, with proprietary penetrators allowing connection to the SCM. Within the SEM housing ambient temperature and pressure are continually monitored and an alarm may be sent to the MCS should abnormal conditions arise.
The subsea control and communication is performed using the OCC and SEM inputs/outputs (I/O). Responses from the surface or subsea units are propagated back to the platform control system (PCS) via a Modbus compliant serial or TCP/IP channel from the MCS. The SEM also runs diagnostics showing the state of all power supplies and communications. Diagnostic tools and displays are available to the operators via the topside MCS.

The system is designed for deployment and intervention by means of a remotely operated vehicle (ROV) or diver intervention using a similar module. Assisted guideline and non-guideline running tools or funnels are available with ROV assistance in very deep water. These feature a simple sliding plate design lock down mechanism.