The Rotork SVM (Smart Valve Monitoring) system has been selected to provide a networked solution for digital valve monitoring and partial stroke testing on a large scale oilfield installation in the Middle East. The system is designed to deliver predictive maintenance information from widely distributed areas for use by the operators to reduce shutdowns and improve overall plant efficiency. This is made possible by the ability of the SVM to be integrated into an existing Ethernet and fibre optic infrastructure, enabling over one hundred monitored valve actuators on wellheads at numerous locations to be networked over distances of ten kilometres or more.
The SVM field control units on this project are attached to the ESD circuits for shut off valves installed in sets of two and four on more than fifty wellheads. Analysis is performed on the SVM server computer in the centralised control room. Communication between the wellhead sites and the computer is fully integrated within the operator’s existing network infrastructure. The SVM field units are incorporated into the Ethernet network that links other equipment and instrumentation at each wellhead site. A fibre optic link is then used to transmit the data to intermediate engineering and control stations at two manifold sites. From these sites, fibre optic links are again used to transmit data from all the wellheads to the centralised control room.
Partial stroke testing (PST) is a function used in a safety instrumented system (SIS) to enable the operator to identify possible failure modes on a shutdown or emergency shutdown (ESD) valve without the need to completely close the valve and hence disrupt the process. Partial stroke testing is an accepted hydrocarbon industry standard technique that is quantified in detail by regulatory bodies such as the IEC and ISA.
