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1. Properties of the medium: name of the medium, specific gravity, viscosity, corrosivity, 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 in the piping system can be ignored in the process flow, but 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 water intake tank to the pressure tank, etc.). If necessary, the device characteristic curve should also be prepared. When designing and arranging pipes, the following points should be taken into account: 1. Select the pipe diameter appropriately. A larger pipe diameter results in a lower flow velocity at the same flow rate, thereby reducing frictional losses; however, it increases costs. A smaller pipe diameter leads to a sharp increase in frictional losses, which in turn requires a pump with a higher head pressure, higher power consumption, and increased costs as well as 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 handle. 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 pipes, with the angle being as large as possible, ideally greater than 90°. 4. A valve (such as a ball valve or globe valve) and a check valve must be installed on the discharge side of the pump. Valves are used to adjust the operating point of the pump, while check valves prevent the pump from rotating in reverse when the liquid flows backward, thus protecting the pump from water hammer effects. (When the liquid flows back, a huge reverse pressure is generated, which can damage the pump.) When determining the flow rate and head, Richter reminds you to pay attention to the following: 1. If the minimum, normal, and maximum flow rates are 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