Open-flow system monitors valves

Offshore staff

Crane Valve Services, a Crane Co. company, says its open-flow ValveWatch ESD valve monitoring system helps boost oil and gas platform production.

According to Crane, the patented technology listens to the flow of oil/gas at the emergency shutdown (ESD) valves. The system sends the sounds of oil/gas flow to an onshore monitoring center, and translates them into images to signal smooth operations, caution, or alarm without any interruption to production.

"Production can be increased by performing leakage verification under open flow to eliminate test time with the valve closed, recovery time, and shut-ins. Production in the US, where leakage verification testing is required monthly, stands to benefit significantly," said Kirk Kelhofer, president of Crane Valve Services, says.

The invention of the monitoring system began with pioneering work by Crane Valve Services in conjunction with Norwegian oil companies to develop technology to protect human life and the environment, reducing the risk of events like those contributing to the Piper Alpha disaster. Now, several oil and gas producers in Norway use the system to perform leakage verification and assess valve performance. As a predictive maintenance tool, the system enables oil companies to plan maintenance around specific problems, Crane says.

The system uses dynamic pressure transducers installed in the flow path and the valve cavity, providing information necessary to evaluate leakage, the company says. A strain sensor on the ESD valve yoke or stem, combined with static pressure sensor installed on the actuator, provides information on actuator performance.

Crane developed a prototype system in 2000, installed it in 2001, and production tested it by 2003. Crane has the system on 26 valves in the North Sea. The second generation, including a wireless option, will be available in the 3Q 2005.

5/11/05