ATEX-rated valves

ATEX- rated electrically actuated ball valves are providing the safe shut off of heating oil and diesel fuels at multiple depots operated by one of the UK’s largest fuel distributors.
The flow and level measuring specialist Severn Instruments was formed in 1991 to supply specialised process control and gauging instrumentation. The full range the company supplies, includes temperature control systems, tank content sensors, flow monitoring equipment, level measurement equipment and associated products.
Severn Instruments oversees complete projects, from project development, through to installation and servicing, providing the maximum customer security that results from a single source responsibility supplier. ATEX- rated electrically actuated ball valves are employed by Severn Instruments, as part of the company’s tank overfill protection alarm system (TOPAS). The TOPAS system is critical to safe and efficient operation at fuel depots, as fuel spillages are potentially hazardous and cost around £1,000 per litre to clean up.
Severn Instruments has a contract from the fuel distributor to install its TOPAS system in depots right across the UK. So far, the company has installed the system at 25 depots, with many more to come. “The tanks at the depots where we are fitting our TOPAS system range from 50,000-litres up to-1,000,000 litres,” said John Roberts, Owner of Severn Instruments. “With such large volumes, the depot operators have to be very careful of overfilling of tanks during deliveries. This is where our TOPAS system comes in. After checking in, drivers delivering fuel to the depot connect their hose to the appropriate tank; this could be Kerosene (heating oil) or white or red diesel. The driver then presses a button on a central control panel to test the tank alarm system. Normally this is set at 97% of volume, 2% above the normal gauging level of 95%. If the alarm sounds, then the gauging system is operative and the filling cycle begins. However, if for any reason the filling exceeds the 95% level, the alarm system blasts and signals the Burkert 8804 valves to close in a timed sequence of less than 30-seconds – this to give time to switch the pump off – preventing any fuel spilling over the top of the tank.” “When we won this contact we knew that we needed a highly reliable, IP67 rated, ATEX shut-off valve that would operate seamlessly with our TOPAS system. Burkert’s 8804 valve ticked all of these boxes; we were also recommended to use Burkert on the project, and we know from experience that their equipment is very good.” The Type 8804 valve as used by Severn Instruments is tailor-made for the application; it is suitable for use with aggressive media, such as fuel oils and diesel, and for operation in arduous conditions, thanks to an IP67 ingress rating. ATEX-rated, the 8804 integrates a small electrical rotary actuator with adjustable limit switches and a manual override, a visual indicator into a single compact, and robust assembly that is easy to install in restricted spaces.