Chemical pump in the face of corrosion what need to pay attention to

1. Material selection principle of pump

In the selection of centrifugal pump model, correctly determine the material of centrifugal pump is to ensure the safe operation of centrifugal pump bai line and prolong the service life of the pump an important factor. The selection of materials to consider the impact of various factors from various aspects, so as to select the most appropriate materials.

(1) the nature of pump transmission medium and pump operating conditions, such as temperature, pressure, corrosion, viscosity, whether it contains solid particles. In addition, we must consider whether there are other special situations, such as the pharmaceutical and food industry requires that the medium be particularly clean, to prevent the pollution of metal ions, and the pump that contains solid particle medium requires the material to wear well.

(2) The mechanical properties of the material should be suitable for the requirements of the pump. Reflect the material mechanical properties of the indicators are many, the material used for the pump, mainly considering the strength of the material, steel, hardness, plasticity, impact toughness and fatigue resistance.

(3) The processing technology performance of the material is directly related to the manufacture and installation and maintenance of the pump. Centrifugal pump impeller, shell, balance plate and other parts are made of metal materials cast, and then mechanical processing, some parts also heat treatment.

The performance of material processing technology also directly affects the use of materials and pump costs.

(4) The quality of corrosion resistance is an important issue that can not be ignored in the selection of pump materials. For petrochemical production industry, pump corrosion resistance is particularly important.

2 commonly used corrosion resistant pump material selection

In petrochemical production, acid, alkali and other corrosive liquid materials are often encountered. The centrifugal pump used to transport this kind of material is collectively referred to as corrosion resistant centrifugal pump, the type of this kind of pump is represented by F, its working principle and centrifugal pump is similar, its corrosion resistance is mainly determined by the material properties of the manufacture of this kind of pump.

Most of the corrosion resistant pump can be corrosion resistant mainly depends on the material of the flow parts of the pump, for corrosion resistant pump, according to the different transmission medium, choose the material of the flow parts of the pump. Such as 1Cr18Ni9Ti can be used for low concentration nitric acid at room temperature and other oxidizable acid, alkali and weak corrosive medium: 0Cr18Ni12Mo2Ti is most suitable for conveying high concentration nitric acid at room temperature, but also can transport sulfuric acid, organic acid and other reducing medium: gray cast iron HT200 is suitable for concentrated sulfuric acid; Plastic has a wide range of application, such as ptfe and fep with reasonable formula, mold, processing a variety of materials, corrosion resistant plastic pump has strong corrosion resistance, and has high mechanical strength, not aging, and the advantages of no toxin decomposition, is an ideal equipment to transport all kinds of strong, weak acid, including ptfe is one of the best corrosion resistant materials, Basically can resist any acid, alkali medium corrosion, known as the king of plastic. Ceramics, enamel, glass and so on are also used in some specific occasions to make corrosion resistant pump flow components.