The self-priming pump is a kind of pump equipment that does not need to install the bottom valve in the pipeline. It only needs to ensure that the pump can store the quantitative dosing fluid before work to meet the work. Different liquids can be self-priming pumps of different materials. Self-priming pump applications for urban environmental protection, construction, fire protection, chemicals, pharmaceuticals, dyes, printing and dyeing, brewing, power, electroplating, paper making, mining and washing, equipment cooling, etc., then self-priming pump selection considerations what? Self-priming pump selection precautions 1, to be strictly for the purchase of pumps. Buying water pump but also test, only three cards can avoid the purchase of all products and inferior products. 2, according to local conditions to buy self-priming pump. 3, to be appropriate over the election pump. After determining the type of pump, to consider its economic performance, with particular attention to the pump head and flow and the choice of supporting power. It must be noted that there is a difference between the head (total head) indicated on the pump label and the head of water (actual head) when it is used, as there is a certain loss of resistance when the water flows through the pipe and the pipe. Therefore, the actual head is generally lower than the total head 10% to 20%, a corresponding reduction in the amount of water. Therefore, the actual use, only by the signs of the head and flow rate of 80% to 90% estimated that the pump supporting the power of choice, according to the signs indicated on the power of choice, in order to make the pump start quickly and use safety, power machine Power can be slightly larger than the pump power required, generally higher than about 10% is appropriate; if there is power, when purchasing a pump, you can press the power of the power machine to buy matching pump. With the increasing influence of self-priming pumps, the selection and use of self-priming pumps have also gradually attracted the attention of many users. Based on the above analysis, we initially understand that self-priming pumps need to strictly comply with the purchase procedures in the selection process, To consider the product environment and so on. Self-priming pump selection is not a simple task. The user needs to work on this, because self-priming pump selection is very important for later work.