DIAPHRAGM VALVE


DIAPHRAGM VALVE

PFA

PFA exhibits theraml characteristics like to PTFE, being able to withstand super low to high temperautures (260℃ Maximum temp. for contionuous use.) It is also transparent and mechamically strong under high temperautre. It is easily workable besides applicable with extrusion molding to the same degree as general thermoset plastics. It is used where purity is important, such a semiconductor wafer baskets, piping couplings and non-corrosive linings. PFA has better mechanical strength at high temperatures than FEP, and excellent moldability for easy processing by extrusion, compression, blow, transfer and injection molding methods. Due to the high bonding strength of the carbon, fluorine and oxygan atoms, PFA demonstrates nearly the same outstanding capabilities as PTFE in temperautres ranging from -200℃ to +260℃.

FEP

FEP is a copolymer of tetrafluoroethylene and hexafluoropropylene. FEP consists of carbon atoms and fluorines atoms, as does PTFE, and has a molecular structure in which one of the fluorine atoms bonded to the carbon atoms. FEP has a lower melt viscosity than PTFE and can be processed like other molten thermoplastic resins by extrusion, transfer, injection, and compression molding. Because the bonding energy between its carbon and fluorine atoms is so high, and because the carbon chain is completely surrounded by fluorine atoms, FEP fluorocarbon polymer retains excellent thermal, electrical, and chemical stability. Therefore, it shows high performance in electrical, chemical, and medical applications in temperatures ranging from extremely low to extremely high (-200℃ ~ +200℃) / -328℉ ~ +392℉ ).

PTFE

The fluorine atoms completely cover the carbon chain backbone and protect the carbon-carbon bond from attack. The fluorine atoms are also responsible for the low surface energy and exceptional frictional characteristics of PTFE. Because of very high melt viscosity, PTFE does not flow above its melting point. It requires speical polymer processing like paste extrusion, compression molding and sintering. Among all the fluoroplastics products, PTFE offers the highest heat resistances at 260℃ (maximum temp. for continuous use). It is not corroded by most chemicals and has good electrical insulation and dielectric characteristics. Moreover, it has a unique non-stick property and the lowest coefficient of friction amongst solids. It is the most widely used fluoroplastics, now found in O-rings, gaskets, baerings, tube, wiring, hot plates and irons because of its non-stick property, as well as chemaical tank linings.


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