Abstract :
It has been recognised for many years that Fieldbus communications will enable the next generation of intelligent field device to be released. It is argued that this new set of tools will have a fundamental effect on the way in which we design, build and operate our process plant. Today´s very competitive market place dictates that we must find methods of reducing the capital cost, and operating cost of plant while increasing productivity and having a more favourable effect on the environment. The process control industry is currently in a unique position of being able to contribute in all of these areas by using an all digital, high speed multidrop communications system to generate a truly distributed data base and control system. The control valve is an excellent example of where added intelligence can yield considerable cost saving at each phase in the plant life cycle. An important cost factor is maintenance, as traditionally it has been necessary to remove the valve from the line to inspect for mechanical wear and determine if maintenance is required. To ensure that no faults are missed, all valves are removed and inspected but often more than 70 per cent require no maintenance. The intelligent valve will continuously monitor its own performance and alert an operator to the fact that it is getting to the end of its useful life or requires maintenance
