In my 28 years in and around the offshore energy environment, I've learned how important a properly functioning valve network is to the safety and operational security of an offshore platform. Experience shows the best way to efficiently and safely assess the viability of the vital emergency shut off valves is with a condition monitoring system.
A valve condition monitoring system relies on sensors attached to or near the valve and actuator assembly to monitor their performance. This can be a combination of strain or pressure sensors that transmit data back to the operator for analysis. An ideal valve condition monitoring system provides a live measurement of the health of the valve, detects and predicts potential failures as well as identifies valves that are in need of overhauling or repair.
The benefits of a valve monitoring system include:
In energy industry, our safety is paramount. If an emergency occurs, pipeline operators both on and offshore rely on critical isolation valves to operate successfully on-demand with absolute reliability. Critical valves may often be installed in remote locations, which can be difficult to access for manual testing and inspection. A failed valve or actuator can halt production without warning and create a dangerous situation for personnel. A valve monitoring system displays the real-time condition of these remote but vital valves and actuators, reporting problems before they create potentially dangerous situations.
A valve monitoring system identifies valves that are in need of overhauling or repair. Today, valve maintenance is performed periodically, typically every one to two years. With active valve monitoring, valve maintenance practice can be moved from a corrective maintenance plan into a predictive maintenance plan based on the development of key maintenance parameters. Valve monitoring can allow these to extend to longer intervals.
The system can also save costs by identifying which valves are in good condition and, therefore, need no replacement or service.
Identifying arising problems early also gives the operator the ability to plan for the required maintenance and spare parts before it becomes an emergency. This increases the "uptime" for a facility or pipeline and reduces production loss.
In incidents where the plant experiences an unplanned shut down, a high quality monitoring system will capture the full operational status and condition of the valve. This test can be utilised as a full proof of functionality, and be directly input into Functional Safety Management reports. This is a valid, cost-effective substitute for scheduled testing.
The last benefit I will point out involves identifying undetected faults in a valve. There are basically two types of faults that can occur with a valve: Dangerous Detected faults (DD) and Dangerous Undetected faults (DU).
The Dangerous Detected faults can be detected by traditional inspection and standard test procedures (partial stroke, time the opening and closing event,etc.). The DU are the faults that may occur which will inhibit the valve from moving to the fail safe position. These faults are seldom found without a condition monitoring system.
To preserve the safety of both people and the production “uptime,” our goal is to move as many DU faults into the DD “area” as possible. A valve monitoring system can do this for you.
In Norway, a valve condition monitoring system is recommended on every offshore platform because of the potential safety risk an improperly maintained valve can create. But this technology can also be utilised in the onshore environment. If you would like to learn more about how ValveWatch, MRC Solberg & Anderson’s condition monitoring system, can deliver proven results for your specific application, visit www.saas.no/valvewatch.
About the Author
Tore Juvik is a mechanical engineer with 28 years of experience in the oil and gas industry and has been with MRC Solberg & Andersen since 1992. He is an expert on valve condition monitoring and valve operations, maintenance and diagnostics. He carries extensive field experience relating to valve trouble shooting and problem solving.