Supplementary loaded safety valves

With Sempell™ supplementary loading will high tightness be accieved up to set pressure as well as small opening and closing pressure differences. Adjustable blow down pressure. Adjustment of set pressure can be done under operating conditions. Control of function of the control cabinet will be done without opening of the safety valve.
One control cabinet can be used for one or more safety valves, usually Series S, for example drum and superheater. The safety valves open as normal spring-loaded safety valve at failure (fail-safe function). The control cabinets are available as electro-pneumatic STE4 or pneumatic STE5 cabinets.