Emerson SIL 3-certified valve assemblies

Emerson has introduced valve assemblies that meet the design process requirements of Safety Integrity Level (SIL) 3 per the IEC 61508 standard. The Fisher Digital Isolation final element solutions are designed to serve the needs of users for shutdown valves in critical safety instrumented system (SIS) applications.

For the user, engineering a safety shutdown valve is a complex task. The normal and upset process conditions must be carefully evaluated and understood when choosing valve and actuator components. In addition, the proper combination of solenoids, brackets, couplings and other critical hardware must be specified and carefully matched to the selected valve. Each of these components must function individually and in concert to operate.

The Digital Isolation assembly is designed to address these and other issues by providing an engineered Digital Isolation shutdown valve assembly, designed for each particular process. The various components are specifically selected to satisfy the application requirements. The entire assembly is sold as a fully tested and certified unit, with a single serial number and associated documentation delineating the details of every part of the assembly.

Because the assembly is built as a complete solution, it is said to have greatly improved PFD rate. In some cases, the failure rate of the assembly will be up to 50% less than the combination of the same valve components purchased individually and assembled by an end user.

This improved PFD results from the assembly being certified as a whole system by exida, to meet their rigorous Remote Actuated Valve Assembly requirements.