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Basic data for pump selection: 1. Characteristics of the medium: medium name, specific gravity, viscosity, corrosiveness, toxicity, etc. 2. The diameter and concentration of solid particles contained in the medium. 3. Medium temperature: (°C) 4. Required flow rate. For general industrial pumps, the leakage within the piping system can be disregarded in the process flow; however, the impact of process changes on the flow rate must be taken into account. If agricultural pumps are used for water conveyance through open channels, leakage and evaporation rates must also be taken into account. 5. Pressure: pressure in the water intake tank, pressure in the water discharge tank, and pressure drop (head loss) in the piping system. 6. Pipeline system data (pipe diameter, length, types and quantities of pipeline accessories, geometric parameters from the suction tank to the pressure tank, etc.). If necessary, the device characteristic curve should also be prepared. When designing and arranging pipelines, the following points should be noted: 1. Select the pipe diameter appropriately. A larger pipe diameter results in a lower fluid velocity and reduced resistance losses at the same flow rate; however, it also increases the cost. Conversely, a smaller pipe diameter leads to a sharp increase in resistance losses, thereby requiring a pump with greater head, higher power consumption, and ultimately higher costs and operating expenses. Therefore, a comprehensive consideration from both technical and economic perspectives is necessary. 2. The discharge pipe and its fittings should be designed to withstand the maximum pressure they can bear. 3. The piping layout should be arranged as straight as possible; accessories within the pipes should be minimized, and the length of the pipes should also be reduced as much as feasible. When bends are necessary, the radius of curvature of those bends should be 3 to 5 times the diameter of the pipe, with the angle being as large as possible, ideally greater than 90°. 4. A valve (ball valve or globe valve, etc.) and a check valve must be installed on the discharge side of the pump. Valves are used to regulate the operating point of the pump. Check valves prevent the pump from reversing when liquid flows backward, thereby protecting it from water hammer. (When the liquid flows backward, a huge counterpressure is generated, which can damage the pump.) Regarding the determination of flow rate and head, Reichert reminds you to note the following: 1. If the minimum, normal, and maximum flow rates have been specified in the production process, the maximum flow rate should be taken into consideration. 2. If only the normal flow rate is specified in the production process, a certain margin should be considered. For high-flow, low-head pumps with ns>100, the flow margin is set at 5%, for ns