How to choose the material of chemical pump
Garden Deer Lights,Garden Flamingo Lights,Garden Crane Lights,Garden Giraffe Lights Sichuan Kangruntengpu Photoelectric Technology Co., Ltd. , https://www.tengpulighting.com
How to choose the material of chemical pump All along, corrosion is one of the most troublesome hazards of chemical equipment, a little careless, ranging from damage to equipment, heavy cause accidents and even lead to disaster. According to the statistics, about 60% of the destruction of chemical equipment is caused by corrosion, so the selection of chemical pumps must first pay attention to the scientific material selection. There is often a misunderstanding that stainless steel is a "universal material," no matter what the media and environmental conditions are held stainless steel pump, which is very dangerous. The following for some common chemical media to talk about the selection of the main points: 1. Sulfuric acid: As a strong corrosive medium, sulfuric acid is a very broad use of important industrial raw materials. Different concentrations and temperatures of sulfuric acid on the corrosion of materials vary greatly, for the concentration of more than 80%, the temperature is less than 80 ℃ of concentrated sulfuric acid, carbon steel and cast iron has good corrosion resistance, but it is not suitable for high-speed flow of sulfuric acid, Not suitable for pump valve material; common stainless steel such as 304 (0Cr18Ni9), 316 (0Cr18Ni12Mo2Ti) sulfuric acid medium is also limited use. Therefore, the delivery of sulfuric acid pump valve usually adopts high silicon cast iron (casting and processing difficult), high alloy stainless steel (20 alloy) manufacturing. Fluoroplastic has good resistance to sulfuric acid, the use of fluorine pump (F46) is a more economical choice. Company products are: IHF fluoride plastic chemical pump, PF (FS) strong corrosion-resistant centrifugal pumps, CQB-F Fluorine plastic magnetic pump. 2. Hydrochloric acid: Most of the metal materials are not resistant to hydrochloric acid corrosion (including a variety of stainless steel materials), molybdenum high ferrosilicon can only be used for 50 ℃, hydrochloric acid below 30%. In contrast to metallic materials, the vast majority of non-metallic materials have good corrosion resistance to hydrochloric acid, so lined rubber pumps and plastic pumps (such as polypropylene, fluoroplastic, etc.) is the best choice for the delivery of hydrochloric acid. Company products are: IHF fluoride plastic chemical pump, PF (FS) strong corrosion-resistant centrifugal pumps, CQ polypropylene magnetic pump (or fluorine plastic magnetic pump). 3 .: most of the common metal in the rapid corrosion damage, stainless steel is the most widely used material resistant to all concentrations at room temperature have good corrosion resistance, it is worth mentioning that the stainless steel containing molybdenum (such as 316,316 L ) Corrosion resistance is not only not superior to ordinary stainless steel (such as 304,321), sometimes even worse. For high temperatures, titanium and titanium alloys are commonly used. The company applies products: DFL (W) H chemical pump, DFL (W) PH shielding chemical pump, DFCZ process pump, DFLZP self-absorption chemical pump, IH chemical pump, CQB magnetic pump, 4. Acetic acid: It is one of the most corrosive substances in organic acids. Ordinary steel will be seriously corroded in all concentrations and temperatures of acetic acid. Stainless steel is an excellent acetic acid-resistant material. Molybdenum-containing 316 stainless steel is also suitable for high Warm and dilute acetic acid steam. For high temperature and high concentration of acetic acid or other corrosive media and other harsh requirements, the choice of high alloy stainless steel pump or fluorine plastic pump. 5. Alkali (sodium hydroxide): Steel is widely used in sodium hydroxide solution below 80 ℃ and 30% concentration. Many factories use common steel even under 100 ℃ and 75%. Although the corrosion is increased, the economy it is good. Ordinary stainless steel lye corrosion resistance compared with cast iron has no obvious advantages, as long as the medium allows a small amount of iron mixed with stainless steel is not recommended. For high temperature alkaline use of titanium and titanium alloy or high alloy stainless steel. The company generally cast iron pump can be used for low temperature lye, extraordinary requirements can be used when all kinds of stainless steel pumps or fluorine plastic pump. 6. Ammonia (ammonia hydroxide): Most metals and non-metals in liquid ammonia and ammonia (ammonia hydroxide) corrosion is very slight, only copper and copper alloy should not be used. Most of the company's products for ammonia and ammonia transport. 7. Saline (seawater): ordinary steel in sodium chloride solution and seawater, salt water corrosion rate is not too high, the general need to use paint protection; all kinds of stainless steel also have a low uniform corrosion rate, but may be due to chloride ions caused by local Sexual corrosion, usually 316 stainless steel is better. Various types of chemical companies have 316 material pump configuration. 8. Alcohols, ketones, esters, ethers: Common alcohol medium with methanol, ethanol, ethylene glycol, propanol, ketone medium with acetone, butanone and so on, ester medium has a variety of methyl ester , Ethers, ethers medium ether, ether, butyl ether, etc. They are basically non-corrosive, common materials are applicable, the specific choice should be based on the media properties and related requirements to make a reasonable choice. It is also noteworthy that ketones, esters, ethers are soluble in a wide variety of rubbers and avoid mistakes when selecting sealing materials. There are many other media can not be introduced in this one, in short, should not be arbitrarily and blindly selected materials, should refer to more information or learn from mature experience