Fluoroplastic anti-corrosion valve application points of attention

Abstract: The proper choice and application of anti-corrosion valve lined with fluorine plastic engineering is our concern, we based on years of experience in the field of application of the following views for your reference. Keywords: valve; lined plastic valve lined with plastic valve prices much lower than the corrosion-resistant stainless steel valves and Hastelloy valves, and some strong corrosion medium metal valve can not be used, only lined plastic valve can be used well. But lined plastic valve must be suitable for application, we should pay attention to the application of pressure and temperature and other technical conditions to use a few to my company's products as an example as follows: (1) Fluoroelastomer valve medium temperature: my company's various types of lining Fluoroplastic valves, the use of fluorine plastic F46 (FEP), the use of medium temperature can not exceed 150 ℃ (medium temperature can be short to 150 ℃, long-term use temperature should be about 120 ℃), otherwise, the valve components F46 lining easy to soften, deformation, resulting in the valve is not dead, a large amount of leakage. Such as the user to use the media temperature, a short time temperature below 180 ℃, long time the temperature below 150 ℃, you can choose another fluorine plastic PFA, but the price of PFA fluoroplastic lined expensive, should be matched in advance Inquiry. (2) Do not have negative pressure. Fluorine plastic valve should avoid the use of negative pressure within the pipeline, if negative pressure, easy to cause the valve cavity lined with fluorine plastic layer is sucked out (bulging), shelling, resulting in valve open, shut down failure. (3) pressure, pressure should be controlled within the allowable range. In particular, bellows sealed fluorine Fusu regulating valve, globe valve. Because the bellows is made of PTFE material, high pressure, high pressure, easily lead to bellows rupture. Bellows sealed fluorine Fusu regulating valve, the use of conditions of pressure, high pressure, PTFE packing can be changed to seal. (4) Fluorine plastic valve used in the media conditions should not have hard particles, crystals, impurities, so as to avoid the valve in the open, closed operation of the broken valve spool, the valve seat of fluorine plastic or PTFE bellows. Hard media on the media, crystallization, impurities, the choice of spool, seat can be changed to Hastelloy, but a separate inquiry. (5) Fluorine-plastic valve should be based on the required flow (CV value) the correct choice of the valve size. In the selection, should be based on the required flow (CV value) and other technical parameters to calculate the valve opening and selection of the valve diameter. If the valve diameter is too large, it is bound to make the valve long-term operation in the case of a smaller opening, coupled with the media pressure, so easy to make the valve by the media impact and vibration, valve stem long-term in the media Impact, vibration, and even the valve stem fracture. Users in the matching (optional) all kinds of fluorine plastic valve, as much as possible to understand and master the use of technical conditions in order to choose a good, good, to improve the service life of the valve. In the event beyond the scope of the user to use the technical conditions, should be made to the manufacturer, to discuss.

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