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How should one select an acid-resistant pump? There are some tips to keep in mind. First, it’s necessary to determine what type of acid you’ll be transporting. Below, we introduce several methods for selecting common types of acid-resistant pumps: 1. Pumps for hydrochloric acid: The maximum concentration of hydrochloric acid that is commonly used is 38%. Therefore, for such applications, it’s sufficient for the wetted parts of the pump to be made of plastic. However, if factors like service life and cost-effectiveness are taken into account, one can opt for the FSB fluor alloy centrifugal pump or the CQB-F magnetic drive pump. Both of these pumps offer satisfactory performance at reasonable prices. 2. Pumps for sulfuric acid: Pumps used for sulfuric acid are divided into those for dilute sulfuric acid and those for concentrated sulfuric acid. There is a wider range of options for pumps used with dilute sulfuric acid; these can be engineering plastic pumps, ceramic pumps, or F46/F26 pumps. For concentrated sulfuric acid, only fluoroplastic (F46) pumps can be used, as concentrated sulfuric acid corrodes ordinary engineering plastics, whereas fluoroplastic does not get corroded. It should also be noted that concentrated sulfuric acid has a high density; therefore, when selecting a pump, it is necessary to choose one with an appropriately high motor power. A simple formula for calculating this is “shaft power” * 1.84, which gives the shaft power required for transporting concentrated sulfuric acid. Tips for selecting acid-resistant pumps 3. Hydrofluoric acid: Hydrofluoric acid is highly corrosive; it is recommended to use fluoroplastic magnetic pumps (and it is essential to replace the ceramic components in these pumps with materials resistant to hydrofluoric acid). 4. Nitric acid: For nitric acid transfer pumps, it is also recommended to use fluoroplastic magnetic pumps, and the rubber seals should be replaced with those made of PTFE. 5. Acetic acid: It is one of the most corrosive organic acids. Ordinary steel suffers severe corrosion in acetic acid at all concentrations and temperatures, while stainless steel is an excellent material resistant to acetic acid. 316 stainless steel, which contains molybdenum, can also be used in high-temperature environments as well as with dilute acetic acid vapor. For demanding applications involving high-temperature and high-concentration acetic acid or other corrosive media, high-alloy stainless steel or fluoroplastic magnetic pumps can be selected. Such as CQB magnetic pumps, CQ316L stainless steel magnetic pumps. 6. For saline (seawater) applications, ordinary steel exhibits a low rate of corrosion in sodium chloride solutions, seawater, and brackish water; coating protection is generally required. Various types of stainless steel also have a low rate of uniform corrosion, but local corrosion may occur due to chloride ions. 316 stainless steel is usually a good choice, although it is more expensive. It is recommended to use fluoroplastic centrifugal pumps, such as IHF chemical centrifugal pumps. 7. Sealing: Magnetic pumps utilize a static sealing mechanism, so there is no need to concern oneself with sealing performance. Centrifugal pumps generally employ external bellows-type mechanical seals, which offer good resistance to corrosion and wear; if the medium being transported contains particles, a hard-to-hard mechanical seal can be used.