Corrosion-resistant centrifugal pumps are chemical centrifugal pumps suitable for transporting various corrosive liquids such as strong acids, alkalis, salts, and strong oxidants at any concentration. Commonly used materials are non-metallic materials, such as fluoroplastics. The shell is lined with a metal shell. Polyperfluoroethylene propylene (FEP) and flow parts are all made of plastic alloy (PTFE, FEP). When we are purchasing fluoroplastic corrosion-resistant centrifugal pumps, pump manufacturers will generally ask you whether you want F4 material or F46 material? So how to distinguish these two raw materials?
From the point of temperature resistance:
The material of the corrosion-resistant centrifugal pump F4 is PTFE, the Chinese name: polytetrafluoroethylene, which is an engineering plastic, it has a wide range of high and low temperature use, excellent chemical stability, high electrical insulation, and non-sticky surface. Good lubricity, resistance to atmospheric aging, non-combustibility and self-extinguishing. The relative density is 2.1-2.3, and the glass transition temperature is 327 degrees. Non-stick coatings can be used continuously at 260°C, with a maximum use temperature of 290-300°C, extremely low friction coefficient, good wear resistance and excellent chemical stability. It is widely used in high-temperature (continuous use below 260℃) high-frequency insulation, corrosion-resistant wire and cable, micro-coaxial cable, industrial control cable, and insulated casing wrapped wire.
The material of the corrosion-resistant centrifugal pump F46 is FEP, and the Chinese name is polyperfluoroethylene propylene, which is a modified material of polytetrafluoroethylene. F46 not only has the similar characteristics of PTFE, but also has good processing properties of thermoplastics. The non-stick coating melts and flows during baking to form a non-porous film. It has excellent chemical stability and excellent non-stick characteristics. The maximum use temperature is 200°C. It is mainly used in the coating and sheath of high insulation, high temperature resistance, corrosion resistance wire and cable. It can be used continuously below 200 ℃ in a wide temperature and frequency range. It has a very low dielectric constant, dielectric loss and very low dielectric constant. High dielectric strength. Can not burn in the air (limiting oxygen index>95%, UL94 flame extremely V-0)
The temperature resistance range of F46 is -200℃~270℃, and the temperature resistance range of F4 is -200℃~280℃.
From the color point:
F4 is white and opaque, and F46 is off-white and translucent.
Distinguish from the nature:
PTFE (F4) is polytetrafluoroethylene, which has good temperature resistance and corrosion resistance, and can withstand corrosion by any medium. The color is absolutely white. It is generally used for fluorine-lined pipes, valves, seals, rods, etc., FEP (F46) It is polyperfluoroethylene propylene, the color is transparent, and the corrosion resistance is equivalent to PTFE. It is generally used for fluorine-lined pumps or perfluorinated pumps.
Both F4 and F46 have strong corrosion resistance and chemical stability. The physical properties of F4 material are harder than F46, and the temperature resistance is higher than F46, about 200 degrees, but F4 is more difficult to form, so many parts with complex shapes They are all made with F46. The two are used together to increase abrasion resistance.
FEP (F46) is cheaper, PTFE (F4) is more expensive. Therefore, the corrosion resistance of F4 material is not as good as that of F46. If it is a liquid with strong acid and alkali, we would better choose F46 material.
