Application Areas Of Wafer Type Butterfly Valve

Lined Butterfly Valve The third application area, silo discharge valve
The pressure in this application area is low, because the material accumulation height rarely exceeds 15 meters, that is, about 1.5 bar, and the temperature is between +5 and +50. The working cycle of the valve is determined by the metering process such as bagging or loading, which means that it is usually 20 to 500 working cycles/day, about 6000 times/year. Lower than the corresponding values ​​in other application areas. The material is generally non-sticky - so basically non-oily and non-wetting materials are used. In terms of chemical resistance, the simplest EPDM lining with ductile iron and CF8M valve butterfly will be competent. Many users often ask for a longer and better service life, because the life of these valves usually does not exceed 3 to 6 months. My answer is very simple! The biggest problem in the silo discharge application is not pressure, not temperature, nor high-speed working cycles, but the abrasiveness of the medium, such as cement. We can extend the service life by using very special liners and butterfly materials, such as Hastelloy, etc. - but this will cost ten times the base price and only double the service life in the best case, so this approach is not economical. The other option is to switch to knife gate valves, which still have the disadvantage of being four times the base price and are also slow because knife gate valves are linearly driven and require multi-turn actuators or cylinders to drive them, and their speed is one-tenth that of 90-degree angle actuators. Given this, I usually recommend still using the cheapest butterfly valve with an EPDM liner and CF8M butterfly, and replacing it every 4 to 6 months. In the end, you will find that this is much more economical than any other solution. Above, I have explained my views on the expected service life of butterfly valves and introduced three different material selection methods for different application areas. I hope this will help you choose the right butterfly valve for your production process.