An Innovative Ultradeepwater Subsea Blowout Preventer Control System Using Shape-Memory Alloy Actuators

This paper presents an innovative undersea blowout preventer (BOP) using shape-memory alloy (SMA). The new device using SMA actuators could easily be implemented into existing conventional subsea control system so that they can work solely or as a backup of other methods. Most important, the innovative all-electric BOP will provide much faster response than its hydraulic counterpart and will improve safety for subsea drilling. To demonstrate the feasibility of such a device, a proof-of-concept prototype of a pipe RAM type BOP with SMA actuation has been designed, fabricated, and tested at the University of Houston. The BOP actuator uses strands of SMA wires to achieve large force and large displacement in a remarkably small space. Experimental results demonstrate that the BOP can be activated and fully closed in less than 10s. The concept of this innovative device is illustrated, and detailed comparisons of the response time for hydraulic and nitinol SMA actuation mechanisms are included. This preliminary research reveals the potential of smart material technology in subsea drilling systems.