Pump and pumping stations.pptVIP

Pump and pumping stations Project design 1,the function of pumps: Pumping machinery serve the following purposes in water systems: Lifting water from its source. Boosting water from low-service to high-service areas Draining storm water Transporting sludge or wastewater Types of pumps: Centrifugal pumps ,propeller pumps, mixed -flow Open –impeller, closed-impeller single-stage multistage pumps (displacement pump ;rotary pumps; hydraulic rams; jet pumps; air lifts) How to choose pumping units System heads Pump characteristic Required flow High efficiency Hydraulic characteristics Safety against cavitations Be convenient to manage Low cost Pumps be used widely in the market Energy saving and regulating pumps Is adverse to pumps’curve Output flow in accordance with fluctuations in demand Head Different pumps national standards. for centrifugal pumping efficiency but for Propeller and diagonal pumps. The relationship between Qmin ,Qmax with only a pump , a few of pumps , Pumps with large capacity and low capacity working together will be more efficiency. Exchange impeller is suit for 1.primary run 2.The level of water change largely (over a wide static head range, abstraction engineering) The choice of regulating pump (1) out flow system (2) the number of pumps (3)rate of regulating Inlet and flow course A small pump station Absorbing well (be of medium size) Large impeller ,diagonal pumping stations 前池 forebay (d600mm)吸水池或流道。进水流道 flow passage（大中型，泵通过流道从吸水井中吸水） Protect against vortex and eddy（漩涡，逆流） let flow be stable Critical depth and ABCDF whirl Quantity of air effects the work of Pumps The inlet velocity influence formation of vortex Lay out of pumping stations Variety of collocation pressure pipe and inlet etc (1)相邻机组的基础之间应有一定宽度的通道,以便工作人员通行; (2)对于非水平接缝的水泵,在检修时往往需要将泵轴和叶轮沿轴线方向取出,因此在设计泵站时,要考虑这个方向上有一定的余地; (3)装有大型机组的泵站内,应留出适当的面积作为检修机组之用; (4)泵站内主要通道宽度应不小于1.2m; (5)辅助泵通常安装在泵房内适当的地方,应尽可能不增大泵房的尺寸. 对于吸水管路的要求是