Why the Smart Valve was developed. Damage to fluid systems aboard ships and in other types of facilities impedes damage control efforts, allowing damage to spread and increasing the number of people involved in damage control. The USS STARK experience is representative of Fleet performance today: it took 29 minutes to restore firemain pressure after the missile hit; in the meantime, firefighting could not be conducted and the fire spread. Other problems also result from damage to other types of fluid system. In addition, restoring damaged fluid systems is manpower intensive. Consequently, improving the capability to isolate fluid systems damage is an essential first step to conducting effective damage control with fewer people. Since the valves must function after damage, survivability is an essential requirement. Conventional leak detection technologies are not highly survivable because they depend upon communications among separate points in the fluid system. The Navy and other industries need an isolation valve that does not depend on such communications.

Actual Smart Valve Sensor Data

How the Smart Valve works. The microprocessor continually monitors the valve inlet and outlet pressures and calculates flow rate and direction based on differential pressure. Pressure below a defined set point combined with flow above a defined set point indicate that a rupture (or large leak) has occurred. Using innovative decision tables based on the relative locations of smart valves and pumps, the microprocessor determines if the valve is closest to the rupture. The valves closest to the rupture close first, while the upstream valves wait for a valve downstream to close and restore pressure. If an upstream valve does not sense pressure restored after a predetermined time delay, the upstream valve then closes to restore the system. Laboratory and shipboard testing have demonstrated that the logic is inherently robust and can be applied to a wide variety of valves and actuators in a wide variety of fluid systems. A patent application has been filed for this novel rupture detection and isolation logic.

Benefits of the Navy Smart Valve.
The "device level logic" that requires only data from the valve itself to make the control decision provides several benefits, including:

• Highly survivable.
• Very robust ­ the next valve upstream inherently will operate if the first valve fails; more complex logic is not needed to achieve gradual system degradation as components fail or are damaged.
• "Open" architecture ­ the control logic is highly modular and clearly defined with a simple interface to the rest of the system.

Potential Navy and Commercial applications.
The Navy smart valve would benefit existing and new Navy ships in systems such as the firemain and chilled water systems. Commercial applications in the petrochemical and offshore industries are being pursued by both MPR (the developer of the control logic) and TYCO Flow Control (the developer of the valve hardware).

Acknowledgement. MPR developed the Smart Valve as part of the U.S. Navy's Damage Control Automation for Reduced Manning Program conducted by the Navy Research Laboratory.