The reason for the large noise produced by the long shaft hydraulic pump operation

Corrosion has always been one of the most troublesome hazards of chemical equipment. If it is careless, it will damage the equipment, or even cause accidents or disasters. According to relevant statistics, about 60% of the damage of chemical equipment is caused by corrosion, so in the selection of chemical pump should pay attention to the scientific nature of material selection. There is usually a misunderstanding that stainless steel is a "universal material", no matter what medium and environmental conditions are holding out stainless steel, this is very dangerous. The following for some commonly used chemical media hanlong machinery to talk about the key points of material selection:

1. As one of the strong corrosive media, sulfuric acid is an important industrial raw material with a wide range of uses. Different concentration and temperature of sulfuric acid on the material corrosion difference is great, for concentration of more than 80%, less than 80℃ of concentrated sulfuric acid, carbon steel and cast iron have good corrosion resistance, but it is not suitable for high-speed flow of sulfuric acid, not used as the pump valve material; Ordinary stainless steel such as 304 (0Cr18Ni9), 316 (0Cr18Ni12Mo2Ti) sulfuric acid medium is also limited use. Therefore, the pump and valve for conveying sulfuric acid is usually made of high silicon cast iron (casting and processing difficult) and high alloy stainless steel (20 alloy), but its processing difficult and expensive, so it is not favored by people. Fluorine plastic alloy has very good sulfuric acid resistance, using fluorine lined pump (F46) is a more economical choice. Jinggang pump industry applicable products are: IHF fluorine lined pump, FSB strong corrosion resistant centrifugal pump, IMD fluorine plastic magnetic pump, etc.

2. Hydrochloric acid Most metal materials are not resistant to hydrochloric acid corrosion (including all kinds of stainless steel materials), high ferrosilicon containing molybdenum can only be used for hydrochloric acid below 50℃, 30%. In contrast to metal materials, most non-metallic materials have good corrosion resistance to hydrochloric acid, so lined rubber pumps and plastic pumps (such as engineering plastics, fluorine plastics, etc.) are the best choice for conveying hydrochloric acid. Jinggang pump industry applicable products are: CQB type fluorine plastic non-leakage acid-proof pump, CQF engineering plastic magnetic pump (or fluorine plastic magnetic pump), etc.

3. The nitrate General metal corrosion and damage, mostly in nitric acid was quickly is the most widely used nitric acid resistant stainless steel material, all to room temperature the concentration of nitric acid have good corrosion resistance, it is important to note that the molybdenum stainless steel (e.g., 316, 316 l) of nitric acid corrosion resistance not only no better than ordinary stainless steel (e.g., 304, 321), sometimes even less. For high temperature nitric acid, fluorine plastic alloy materials are usually used. Jinggang pump industry applicable products are: CQB fluorine plastic alloy magnetic pump, FSB fluorine alloy centrifugal pump.

4. Acetic acid it is one of the most corrosive substances in organic acids, ordinary steel in all concentrations and temperatures of acetic acid will be seriously corroded, stainless steel is an excellent acetic acid resistant material, 316 stainless steel containing molybdenum can also be applied to high temperature and dilute acetic acid steam. For high temperature high concentration of acetic acid or containing other corrosive media and other harsh requirements, can choose high alloy stainless steel or fluorine plastic pump. Jinggang pump industry applicable products are: CQB magnetic pump, CQ stainless steel magnetic pump.

5. Alkali (sodium hydroxide) is generally not very corrosive, but the general alkali solution will produce crystallization, so you can choose FSB type fluorine alloy alkali pump equipped with graphite silide 169 material mechanical seal

6. Ammonia (ammonia hydroxide) Corrosion of most metals and non-metals in liquid ammonia and ammonia water (ammonia hydroxide) is very mild, only copper and copper alloys are not suitable for use. Jinggang pump products are mainly used for transporting ammonia and ammonia water. Such as CQF engineering plastic magnetic pump, FSB fluorine alloy centrifugal pump is better

7 salt water (sea water) ordinary steel in sodium chloride solution and seawater, salt water corrosion rate is not too high, generally must use paint protection; All kinds of stainless steel also have a very low uniform corrosion rate, but may cause local corrosion due to chloride ions, usually using 316 stainless steel is better. Jinggang Pump industry all kinds of chemical pump 316 material configuration, such as IH chemical centrifugal pump.

8. Alcohol, ketone, ester, ether common alcohol media methanol, ethanol, ethylene glycol, propanol, ketone media have **, butyl ketone, ester media have all kinds of methyl ester, ethyl ester, ether medium methyl ether, ether, butyl ether, etc., they are basically not strong corrosion, so can choose ordinary stainless steel, Specific selection should also be based on the properties of the media and relevant requirements to make a reasonable choice. In addition, it is worth noting that ketone, ester, ether on a variety of rubber solubility, in the selection of sealing materials to avoid mistakes. It is recommended to choose jinggang inorganic sealing fluoro plastic magnetic pump