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Many materials in the chemical industry are recognized as extremely corrosive.In special working conditions concerned withe the 

chemical industry,it is  important to select the right equipment,pipelines and valves,so as to ensure stable operations.Most corrosive 

media are usually highly  corrosive to metals,and regular metal valves,such as carbon steel and stainless steel valves,will be easily 

corroded.Even special alloys ,such as Hastelloy and Monel,have the chance to be corroded.Apart from this ,special alloy valves are quite

expensive,have a long processing cycle,and may  cause casualties after corrosion.

With the continuous application of new chemical materials and improvement of lining process,fluorine(plastic) lined control valves and shut-off

 valves are favored by manufacturers and users for their outstanding performance in safety,reliability and cost-efficiency.They are more and more 

widely used in highly corrosive media processing in petroleum,chemical,pharmaceutical and other industries.However,fluorine(plastic) lined valves 

cannot adapt to all corrosive working conditions.Just like other valves,it requires expertise to select and use the right fluorine(plastic) lined valves.

The temperature of fluorine(plastic) lined valves should not be higher than 30% ofits upper limit.

According to  public information,the operation temperature of fluorine(plastic)lined valve varies from

different materials:PTFE(-60-150℃）,should PTFE PFA(-60-180℃）,and PTFE F46((-20-120℃）.

However ,the actual temperature will be different because of different materials and pressures.In the 

logn run,the temperature should generally be about 30% lower than the upper limit,otherwise ,the lining

of each component of the valve can easily be deformed,resulting in large leakage or failure to open/close the valve normally.