Fluorine plastic pump should be how to choose

Petroleum and chemical industry occupy a very important position in the national economy. Chemical process pumps are also attracting more and more attention as a key supporting equipment. Due to the complex nature of the chemical medium, coupled with the environmental protection and equipment requirements continue to increase energy consumption, as a chemical manufacturer, how should we select the chemical pump? Should pay attention to what aspects? ... And so on is particularly important. Now combined with the majority of chemical products related to the characteristics of chemical pumps on the selection of common use to do a brief review, hoping to benefit our customers better work in this area. Corrosion-resistant problems For a long time, corrosion is one of the most troublesome hazards of chemical equipment. Slight carelessness can damage equipment and cause accidents or even accidents. According to the statistics, about 60% of the destruction of chemical equipment is caused by corrosion. Therefore, the selection of chemical pumps should 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 out of stainless steel, 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 an important use of a wide range of 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 is usually made of high silicon cast iron (casting and processing difficult), high alloy stainless steel (No. 20 alloy) manufacturing, but its processing is difficult and expensive, so people are not optimistic. Fluoroplastics alloy has very good resistance to sulfuric acid. It is the patented material of Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences. Our company introduced the patented technology in 1985 and the earliest use it to develop and produce corrosion-resistant chemical pump. After the experiment of the Chinese Academy of Sciences, No chemical medium has yet been found to react with it over the applicable temperature range, so using a fluorine-based pump (F46) is a more economical option. Company products are: CQB fluorine plastic magnetic pump, IMD lining fluorine magnetic pump, IHF lined fluorine centrifugal pump, FSB fluorine alloy centrifugal 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 engineering plastics, fluoroplastics, etc.) are the best choice for the delivery of hydrochloric acid. Company products are: CQB fluorine plastic magnetic pump, IMD lining fluorine magnetic pump, IHF lined fluorine centrifugal pump, FSB fluorine alloy centrifugal pump, UHB polyethylene centrifugal pump. 3. Nitric acid: most of the common metals are rapidly corroded in nitric acid damage, stainless steel is the most widely used nitric acid-resistant materials, all concentrations of nitric acid at room temperature have good corrosion resistance, it is worth mentioning that the stainless steel containing molybdenum ( Such as 316,316L) nitric acid corrosion resistance not only not superior to ordinary stainless steel (such as 304,321), sometimes even worse. For high temperature nitric acid, usually using fluorine plastic alloy material. Company products are: CQB fluorine plastic magnetic pump, IMD lining fluorine magnetic pump, IHF lined fluorine centrifugal pump, FSB fluorine alloy centrifugal pump. 4. Acetic acid: It is one of the most corrosive substances in organic acids. Ordinary steel will seriously corrode 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 temperature And dilute acetic acid steam. For high temperature and high concentration of acetic acid or other corrosive media containing harsh requirements, the choice of high-alloy stainless steel or fluorine plastic pump. Such as CQB fluorine plastic magnetic pump, IMD lining fluorine magnetic pump, IHF lining fluorine centrifugal pump, FSB fluorine alloy centrifugal pump. 5. Alkali (sodium hydroxide): The general corrosivity is not very strong, but the general alkali solution will have a crystal, so the optional mechanical seal with graphite 164 material IHF lining fluorine centrifugal pump and FSB fluorine alloy centrifugal pump. 6. Ammonia (ammonia hydroxide): Most metals and non-metals in liquid ammonia and ammonia (ammonia hydroxide) corrosion are minor, only copper and copper alloy should not be used. Most of the company's products for ammonia and ammonia transport. Such as fluorine plastic magnetic pump, fluorine plastic centrifugal pump can be long-term and stable use. 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 pump companies are applicable. 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., their basic corrosive is not strong, so you can use ordinary stainless steel, 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, must not be arbitrarily and blindly in the selection of materials should be more access to relevant information or learn from the mature experience or to our company for more information. Sealing problems No leakage is the eternal pursuit of chemical equipment, it is this requirement contributed to the growing use of magnetic pumps. However, there is still a long way to go without leakage, such as the life span of the magnetic pump isolation sleeve, the material pitting problem, the reliability of the static seal, and the like. Now on the sealing of some of the basic situation is briefly described as follows: 1, the sealing form: For the static seal, usually only two forms of seals and seals, and O-ring seal again the most widely used; for the dynamic seal, Chemical pumps are rarely used packing seal, mainly mechanical seals, mechanical seals and single-sided and double-sided, balanced and unbalanced points, balanced for high pressure medium seal (usually refers to the pressure greater than 1.0MPa) Double-ended mechanical seal is mainly used for high temperature, easy crystallization, viscosity, containing particles and toxic volatile medium, double mechanical seals should be injected into the sealed chamber isolation liquid, the pressure is generally higher than the media pressure 0.07 ~ 0.1MPa, Mechanical seal with easy installation and maintenance, without the need to join the cooling fluid, the price is moderate, chemical pump is widely used in a dynamic seal form. 2. Sealing material: chemical magnetic pump static sealing materials generally use fluoroelastomers, special circumstances, the use of PTFE material; mechanical seal ring static material configuration is more critical, not the best cemented carbide and cemented carbide on the best , The high price is on the one hand, there is no hardness difference between the two is not reasonable, it is best treated according to the characteristics of different media, the mechanical seal of our company have silicon carbide on the PTFE (basic configuration), silicon carbide on silicon carbide , Alumina ceramic on PTFE, silicon carbide on alumina ceramics, cemented carbide on cemented carbide for users to choose to configure use. Viscosity Problem The viscosity of a medium has a significant effect on the performance of the pump. As the viscosity increases, the lift of the pump drops, the head and flow of the optimum conditions decrease, and the power rises, resulting in lower efficiency. General parameters on the sample are the performance of the transport of water, when the transport of viscous media should be converted (different viscosity correction factor can be found in the relevant conversion chart). For the viscosity of the pulp, paste and viscous liquid delivery, the proposed selection of mortar pump, my company's UHB-ZK corrosion-resistant mortar pump can be applied to the viscosity or with corrosive media particles. Pump Selection Principles Design Institute in the design of equipment, to determine the pump usage and performance parameters and select the pump. First of all, this choice from the choice of pump type and form of the beginning, then what principle to choose the pump? What is the basis? 1, Make the type and performance of the selected pump meet the requirements of process parameters such as device flow, head, pressure, temperature, NPSH, suction and so on; 2, Must meet the requirements of medium characteristics, Or expensive medium pump, shaft seal required reliable or adopt 【Purchase】 fire pump, spray pump, sewage pump 【Purchase】 bearing accessories 【Purchase】 air lock valve 【Purchase】 signal amplifier 【Purchase】 valve 【Purchase】 Centrifugal pump 【 Purchase] vertical multi-stage pump [Procurement] fuel tank [Procurement] speed control variable frequency motor