Curtiss-Wright offers a unique service for evaluation of critical valves in nuclear power plants. Our Valve Maintenance Optimization Program (VMOP) is backed by several current and former nuclear plant valve program owners with extensive experience in valve condition monitoring and maintenance.

A key element of VMOP is the Curtiss-Wright application and advanced vibroacoustic sensors to detect valve damage or wear. These values recorded during testing are critical to the VMOP’s ability to determine valve condition and justify extending maintenance cycles.

Testing involves attaching sensors to the valve and performing valve cycling or lift testing. A Proprietary Curtiss Wright VMOP Sensor value is measured and plotted, and the post-lift values are entered into algorithms to assess otherwise undetected damage and overall valve health. These recorded values are valuable in determining future possible leakage increases that may occur after the valves are installed.

Valves, primarily safety relief valves, are removed from plants and sent to an off-site testing facility. Before returning the valves to the plant, a verification is performed to determine there is no excess leakage by performing a “cold bar” test. While the valve is under pressure, a cold bar is inserted downstream of the valve to see whether moisture forms on the surface. For well over a decade, VMOP has been supplementing the cold bar test by attaching Curtiss Wright sensors at strategic locations on valves being tested and has developed a high level of confidence in the correlation between the measured energy and future performance.

If high energy levels are detected during testing, the valves have additional maintenance such as seat lapping performed on them. Additionally, VMOP has been successfully applied to justify extending the testing and maintenance cycles at several plants. VMOP provides a powerful benefit to the industry to avoid costly unplanned outages and possibly even reduce testing and maintenance costs.

• Access to multiple current and former nuclear plant valve program owners and valve testing industry experts
• Curtiss Wright VMOP testing values compared to more than 1000 historical tests
• Recommendations for program changes based on test results
• Access to industry best practices, such as lapping techniques, spring changes, seat plating, and more
• Assistance justifying extending maintenance cycles internally, and when applicable, to the NRC