The two hydraulic-diagnostic methods detailed in this paper can monitor the "health" of a subsea hydraulic-control system, diagnose or predict a system problem (particularly leaking or clogging problems), and locate its source by using readily available valve-signature data.
The methods were tested in a laboratory environment using a hydraulic system with simulated clogging and leaking mechanisms. Leak detection was performed using both signature-matching and mass-balance methods. The results showed a mean accuracy of 93% for mass-balance method and 82% for the signature-matching method. Clog detection by signature matching showed high accuracy in the controlled laboratory condition. The difference between the simulated and actual clogging is within 1%.
The methods provide a monitoring tool for detecting and locating potential leaks, blockages, and other system changes or anomalies, which could be used to estimate the potential high cost of intervention, possible downtime, and lost revenue.
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