The sanitary PTFE sealing Butterfly valve is one kind of center sealing valve, the high class white colour PTFE is used as  clack seat sealing, the PTFE material within excellent chemical resistance and lubricity to ensure can be used for widely conditions than common rubber sealing material and lightly operation. The main advantage of the valve is that can prevent the rubber drop off  which will damage/ the materials, the valve can be used in sterile pharmacy power, powered milk, starch, sugar industry etc...