管道離心泵的安裝技術(shù)關(guān)鍵在于確定離心泵安裝高度即吸程。這個(gè)高度是指水源水面到離心泵葉輪中心線(xiàn)的垂直距離，它與允許吸上真空高度不能混為一談，水泵產(chǎn)品說(shuō)明書(shū)或銘牌上標示的允許吸上真空高度是指水泵進(jìn)水口斷面上的真空值，而且是在1標準大氣壓下、水溫20℃情況下，進(jìn)行試驗而測定得的。它并沒(méi)有考慮吸水管道配套以后的水流狀況。而水泵安裝高度應該是允許吸上真空高度扣除了吸水管道損失揚程以后，所剩下的那部分數值，它要克服實(shí)際地形吸水高度。水泵安裝高度不能超過(guò)計算值，否則，離心泵將會(huì )抽不上水來(lái)。另外，影響計算值的大小是吸水管道的阻力損失揚程，因此，宜采用短的管路布置，并盡量少裝彎頭等配件，也可考慮適當配大一些口徑的水管，以減管內流速。應當指出，管道離心泵安裝地點(diǎn)的高程和水溫不同于試驗條件時(shí)，如當地海拔300米以上或被抽水的水溫超過(guò)20℃，則計算值要進(jìn)行修正。即不同海拔高程處的大氣壓力和高于20℃水溫時(shí)的飽和蒸汽壓力。但是，水溫為20℃以下時(shí)，飽和蒸汽壓力可忽略不計。從管道安裝技術(shù)上，吸水管道要求有嚴格的密封性，不能漏氣、漏水，否則將會(huì )破壞離心泵進(jìn)水口處的真空度，使離心泵出水量減少，嚴重時(shí)甚至抽不上水來(lái)。因此，要認真地做好離心泵管道的接口工作，保證管道連接的施工質(zhì)量(圖\文www.lfsvw.com/index.asp)。 中譯英： Pipeline centrifugal pump / installation technology is the key to determine the suction centrifugal pump installation height. This highly refers to the water surface to the centrifugal pump impeller centerline vertical distance, and it allows suction vacuum height can not be confused, pump product brochures or nameplate marked on the allowable suction vacuum pump inlet section refers to the value of the vacuum on, and was in the 1standard atmospheric pressure, water temperature 20℃test and measurement, the. It does not take into account the suction pipe supporting later flow condition. And the pump mounting height should be allowed to deduct the suction vacuum suction piping loss of lift, the remaining portion of numerical value, it is to overcome the real terrain suction height. Pump mounting height should not exceed the calculated value, otherwise, centrifugal pump will be pumped to not Sheung shui. In addition, affect the calculation value is the size of the suction piping resistance loss of lift, therefore, should adopt the most short circuit arrangement, and minimize the loaded elbow parts, may also be considered appropriate with a larger caliber pipe, to reduce the flow velocity in the tube. It should be noted, the pipeline centrifugal pump installation site of the elevation and water temperature is different from the test conditions, such as local altitude 300 meters of above or by pumping water temperature is over 20 ℃, then the calculation of value must be amended. The different elevation at atmospheric pressure and temperature of above 20 DEG C saturated steam pressure. However, the water temperature is 20℃, the saturation vapor pressure is negligible. From the pipeline installation technique, water pipes required strict sealing, not leakage, water leakage, otherwise it will destroy the centrifugal pump inlet vacuum degree, the centrifugal pump to reduce the amount of water, serious when can't even afford Sheung shui. Therefore, to seriously do a good job of centrifugal pump pipeline interface, ensure the construction quality of pipe connection.
