Several Problems Should be Noticed in Application of Fluorine Plastic Valve
July 15, 2021
Reasonable selection and application of fluorine-plastic anti-corrosion valve is a project on the concern of everyone, according to our customers many years of field experience in the application of the following considerations for your information. Keywords: valve, lined with fluorine plastic Fluorine plastic anti-corrosion valve in petroleum, chemical, pharmaceutical, metallurgical, power and other industries exposed to acid and alkali and other corrosive media device has been widely used, but how to choose the right, with Fluorine-plastic valve good, according to our vast number of users on-site application of experience, selection of anti-corrosion valve lined with plastic when dealing with the media temperature, pressure, pressure and other conditions of use made the following precautions: 1, Medium temperature: Fluorine plastic Fluoroplastic (FEP) is used by our company. The temperature of the medium used can not exceed 150 ℃ (medium temperature can reach 150 ℃ for a short time), the long-term use temperature should be controlled at 120 ℃), otherwise, the parts of the valve lining F46 easy to soften, deformation, resulting in the valve is not dead, a large amount of leakage. Such as the use of medium temperature short time temperature below 180 ℃, the long time the temperature below 150 ℃, you can choose another fluoroplastic-PFA, but lining PFA Fluoroplastics than lining F46 in the price more expensive . 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, pressure, pressure drop, easily lead to bellows rupture. Bellows sealed fluorine Fusu regulating valve, the use of conditions of pressure, pressure, can be changed to PTFE packing 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 the operation of broken spool, the valve seat of fluorine plastic or PTFE bellows. Hard media on the media, crystallization, impurities, the election, the spool, valve seat can be used Hastelloy. 5, lined with fluorine plastic valve should be required by the 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 should be used in the path and the valve opening degree, such as the valve diameter is too large election, the valve is bound to make the long-term in the smaller degree of opening The case of running, coupled with the pressure of the medium, so easy to make the valve spool, rod by the impact of the media so that the valve vibration, valve rod long-term impact in the medium, and even the valve stem fracture. Users in the selection of various types of fluorine plastic valve, should be as much as possible to understand and master the use of technical conditions in order to select a good, good, to improve the service life of the valve. In the face beyond the scope of the use of technical conditions, should be made to the manufacturer, to discuss, to take appropriate measures to be resolved.
