Valves in action -
Pressure reducing valve DM 618Z
Cereal production – Steam pressure reduction for a honey tank heater
Regardless of whether they are energy providers at the beginning of a busy day or only a snack in between meals: cereal products have become vital for our everyday life. Although the available flavors are confusingly varied, bee honey still is an important ingredient for many of these sweet meals.
Raw materials and ingredients are of various consistencies and often expose the foodstuffs industry to great challenges: For example during the transport of grain, large amounts of dust are released. Honey, that enhances the taste of popped grains or cereal bars, loses its flowability under cooler temperatures and transforms into a viscous mass. To prevent this from happening, honey must continuously be heated to a temperature level of approx. 30 to 40 °C.
A leading company in the foodstuffs industry fabricates semi-finished and finished grain products. In the production plant there is a tank of approx. 40 m³ filled with honey which is constantly heated in order to keep the tank content capable of being pumped. In the heating circuit, a steam generator produces water steam with a pressure of 8 bar absolute. In the downstream steam supply line, the pressure of the generated steam is reduced to 4 bar absolute with the help of the pressure reducing valve Mankenberg DM 618Z and flows through a ball valve that opens pneumatically as soon as the temperature falls below 40 °C. After that the steam flows into a heat exchanger, condenses there and dissipates the heat to the environment. The arising condensate is separated in a steam trap, flows back in the return line to the condensate collector and is then re-supplied to the steam generator.
The self-acting pressure reducing valve DM 618Z reduces the steam pressure downstream of the valve to the suitable plant pressure of 4 bar absolute. The sturdy and low-maintenance control valve can withstand inlet pressures of up to 40 bar and features very favourable flow dynamics. The valve body is made of cast steel, the medium-wetted internal parts are of corrosion-resistant stainless steel (1.4404 / SS316L). Therefore, this metallic-sealed control valve is ideally suited for this steam application.
