Things to keep in mind when selecting corrosion-resistant magnetic pumps – what you need to know.

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As the name implies, a corrosion-resistant magnetic pump is a pump with corrosion-resistant properties, primarily used for transporting corrosive liquids. It is a type of pump that is widely used in general-purpose magnetic pump systems. 　　Currently, in the domestic market, corrosion pumps used for transporting corrosive liquids are mostly made of stainless steel, as this material offers advantages such as a wide range of corrosion resistance, superior performance, ease of maintenance, and simplicity of operation. 　　Acid- and alkali-resistant self-priming pumps are suitable for pumping, recovering, and discharging various chemically corrosive acids, alkalis, and wastewater. They are widely used in industries such as electroplating, electronics, chemicals, leather processing, dyeing and finishing, as well as in the treatment of waste gases. The pump heads in the magnetic pump series are connected to the motor via couplings, and the high-power models are highly favored by users requiring high flow rates. On the basis of having the basic data for selecting corrosion-resistant pumps, the following aspects should be taken into consideration when choosing such pumps: 1. The process flow in which the pump will be used. The basic parameters of the pump, such as flow rate and head, should be determined appropriately based on the requirements of the process. Generally, normal wear and tear of the pump as well as changes in its rotational speed can lead to a decrease in head pressure; therefore, when selecting a magnetic pump, it is advisable to leave a margin of 2% to 5% in terms of head pressure, with this figure not exceeding 10% in any case. The basic principle is to ensure that the pump operates within its efficient range. Additionally, the process allows for obtaining information on the pump inlet conditions, which can be used by the computing device to determine the net positive suction head. 2. Corrosivity of the medium and selection of materials. Due to the wide variety of chemical media and their diverse properties, accurate characteristic parameters are required, especially those related to corrosivity, concentration, volatility, vapor pressure, viscosity, density, etc. These properties are closely related to the selection of materials; not only metal materials need to be considered, but also the interaction between non-metallic materials and the media must be taken into account. 3. Temperature of the medium. Temperature has a significant impact on the selection of the structure for chemical process pumps; aspects such as the method of supporting the pump body and the design of the cooling (or insulation) system are all closely related to the temperature of the medium being transported. 4. Selection of the spindle seal and its auxiliary systems. 　　 Based on analysis of actual cases, spindle seal failures caused by unit faults account for a high proportion of all failures, sometimes exceeding 30% to 40%. Therefore, the selection of the spindle seal is crucial. In addition to the physicochemical properties of the medium, two important parameters must also be understood: the pressure in the sealing chamber and the temperature of the medium within that chamber.