1.0 水泵基礎(chǔ)-ITT 水泵培訓(xùn)資料

1、PUMPSTheory and application水泵基礎(chǔ)將液體提升到一定高度的機(jī)械(將電能轉(zhuǎn)化成機(jī)械能)水泵培訓(xùn)資料(一.1）WHAT IS A PUMP? 水泵是甚麼?Defined as:.a machine to transfer a fluid運(yùn)送流體的機(jī)器按用途分:空調(diào)泵.消防泵,給水泵.潛水泵.排污泵等按結(jié)構(gòu)分:管道泵 一般為立式單級(jí)泵,進(jìn)出口處于水平面且相等端吸泵,側(cè)進(jìn)上出雙吸泵(中開泵),側(cè)進(jìn)側(cè)出直聯(lián)泵 泵頭與電機(jī)使用同一根軸承長(zhǎng)聯(lián)軸器泵潛水泵水泵分類1水泵分類2按介質(zhì)分:清水泵 介質(zhì)清水且無溫度要求熱水泵 介質(zhì)清水溫度要求90C污水泵 介質(zhì)污水油泵 介質(zhì)為油 油溫100

2、C為熱油泵油分輕油和重油我們的泵基本只能輸送輕油化工泵 介質(zhì)為酸堿等化工液體按材質(zhì)分:鑄鐵泵.不銹鋼泵.青銅泵.塑料泵等按級(jí)數(shù)分:單級(jí)泵.多級(jí)泵一. 泵體,又稱為泵頭包括: 泵殼,葉輪,機(jī)械密封，軸承 密封: 材質(zhì)為石墨/陶瓷/碳化鎢(硅)部分用途依然應(yīng)該使用填料密封(如消防)二. 電機(jī),又稱為馬達(dá)三. 其它部分如臥式長(zhǎng)聯(lián)軸器泵包括聯(lián)軸器,底板等水泵組成Centrifugal Impeller Types離心泵葉輪種類參數(shù)(1)流量(Q) 單位時(shí)間內(nèi)的出水量單位:噸/小時(shí)=T/h 升/秒=L/s 1T/h=3.6L/s(2)揚(yáng)程(H) 將液體提升的高度或出口的壓力單位:米=M 壓力習(xí)慣用公斤表

3、示 1KG=1BAR=10M(3)液體介質(zhì)分清水.熱水.污水.油.其它化工液體,水泵只是一種習(xí)慣說法,不一定只輸送水,尤其化工泵須知道液體PH值,濃度,比重,粘度等.(4)介質(zhì)溫度(5)承壓(指水泵正常運(yùn)行所能承受的最大壓力)選型基本要素 - 1轉(zhuǎn)速(R) 單位:RPM=轉(zhuǎn)/分鐘 電機(jī)每分鐘轉(zhuǎn)得速度2900轉(zhuǎn)電機(jī)習(xí)慣稱為2級(jí)電機(jī),1450轉(zhuǎn) 電機(jī)習(xí)慣稱為4級(jí)電機(jī)空調(diào)泵多為噪音比較低的1450RPM,供水泵多為2900RPM電壓(T)通常分三相380伏 3X380V 單相220伏 1X220V通常只有小型水泵才有220V.水泵形式:立式或臥式材質(zhì)要求:鑄鐵,不銹鋼,青銅等是否具有自吸功能其它重要

4、參數(shù)功率(N) 單位:KW 通常指電機(jī)輸出功率P2赫茲:國(guó)內(nèi)為50HZ 國(guó)外多為60HZ防護(hù)級(jí):IP44/54/55/68密封級(jí):B/B3/F*氣蝕余量其他要素-1PUMPING SYSTEMS “CAPACITY ”水泵系統(tǒng) “流量”The amount of liquid flowing through a pumping system is known as the capacity or flow rate流量是液體流過水泵系統(tǒng)的量Typical units used 使用單位:m3/h or m3/s l/s or l/ming.p.m.us g.p.m.PUMPING SYSTEM

5、S “CAPACITY ”水泵系統(tǒng) “流量”PUMPING SYSTEMS“ STATIC HEAD ”靜揚(yáng)程The components of Static head are the elevation between :- the surface of the liquid at the point of suction and at the point of discharge靜揚(yáng)程是液體於進(jìn)水點(diǎn)及出水點(diǎn)之距離Static head also accounts for the pressure differential between the point of suction and t

6、he point of discharge靜揚(yáng)程亦說明進(jìn)水點(diǎn)與出水點(diǎn)之壓差Static head does not vary with capacity靜揚(yáng)程不會(huì)隨著流量而改變ITT FluidPUMPTo Loading RackDN 80 (3”) Pipe6 m6 m4.5 m6 m0.6 mIn this example the static head (Hs) is equal to 靜揚(yáng)程等於:4.5 + 0.6 - 3 = 2.1 mHsExample 2 例子 2PUMPING SYSTEMS “ STATIC HEAD ”靜揚(yáng)程PUMPING SYSTEMS “ DYNAMI

7、C HEAD ” 動(dòng)揚(yáng)程A pump must overcome the resistance of a pumping system in order to cause the liquid to flow completely through the system水泵需克服水泵系的阻力使液體流動(dòng)Resistance to liquid flow is known as a pumping systems Dynamic Head系統(tǒng)的動(dòng)揚(yáng)程就是對(duì)於液體流動(dòng)的阻力Pump水泵Resistance阻力Head 揚(yáng)程ITT GroupDynamic head losses are those l

8、osses that are realised once fluid begins to flow through the pumping system動(dòng)揚(yáng)程是當(dāng)液體開始流動(dòng)時(shí)系統(tǒng)的實(shí)際壓損Dynamic head losses are a function of capacity 動(dòng)揚(yáng)程會(huì)隨著不同流量而變化3.5 bar (50 psi)2.1 bar (30psi)PUMPING SYSTEMS “ DYNAMIC HEAD ” 動(dòng)揚(yáng)程A typical friction loss table for piping illustrates friction losses as a func

9、tion of capacity, pipe diameter, pipe length and viscosity 磨損表顯示出磨損跟流量, 管道直徑, 管長(zhǎng)及黏度的關(guān)係speedWater (viscosity = 1 cSt)speedLubricating oil SAE40 (viscosity = 150 cSt)PUMPING SYSTEMS “ FRICTION HEAD LOSSES ”磨損ITT FluidPUMPING SYSTEMS “ FRICTION HEAD LOSSES ”壓損PUMPTo Loading RackDN 80 (3”) Pipe6 m6 m4.5

10、 m6 m0.6 m6 mHsExample 2In this example the friction losses (Dp) is equal to磨損等於:Flow 流量= 800 l/minTwo elbows 90 (equivalent length)2個(gè)相同長(zhǎng)度90彎頭= 2 x1.5 = 3.0 mPipe losses 管道損失= (6+6+4.5+6)+3.0)x(10/100) = 2.55 mLoading rack losses負(fù)載損失= 2.8 m Total friction losses 總磨損= 2.55+2.8 = 5.35 m PUMPING SYSTEM

11、S “TOTAL DYNAMIC HEAD”總揚(yáng)程Dynamic head represents the resistance of a pumping system while the pumped fluid is in motion動(dòng)揚(yáng)程是液體流動(dòng)之後系統(tǒng)的阻力Static head is the resistance of a pumping system before the liquid is set into motion 靜揚(yáng)程是液體流動(dòng)之前系統(tǒng)的阻力Now what we have to do ?The systems total dynamic head is simply

12、 簡(jiǎn)單地說:Static Head 靜揚(yáng)程+ Dynamic Head 動(dòng)揚(yáng)程 = Total Dynamic Head 總揚(yáng)程PUMPING SYSTEMS “TOTAL DYNAMIC HEAD”總揚(yáng)程PUMPTo Loading RackDN 80 (3”) Pipe6 m6 m4.5 m6 m0.6 m6 mIn this example the total dynamic head (TDH) is equal to 總揚(yáng)程:Static head 靜揚(yáng)程= 2.1 m Dynamic head 動(dòng)揚(yáng)程= 5.35 m Total dynamic head 總揚(yáng)程= 2.1+5.35

13、 = 7.45 mExample 2PUMPING SYSTEMS “TOTAL DYNAMIC HEAD”總揚(yáng)程ITT Fluid Technology - Commercial Products GroupPUMPING SYSTEMS 水泵系統(tǒng) 其他System LayoutBlueprintsIt is a good system design to include suction and discharge valves in the system. 良好的系統(tǒng)應(yīng)有進(jìn)口及出口閘閥Isolating the pump for maintenance considerations以便維修

14、A discharge check valve may also be required in high discharge head applications (to prevent water hammer) 安裝止回閥以防水鎚現(xiàn)象Using the discharge valve as a throttling valve to control the pump 使用出口閘閥控制水泵ITT Fluid Technology - Commercial Products GroupPUMPING SYSTEMS “ SYSTEM CURVE ”系統(tǒng)曲線A System Curve is a

15、graphical representation of the resistance behaviour (TDH) of a pumping system over its entire capacity range系統(tǒng)曲線是用來表示系統(tǒng)的總揚(yáng)程跟流量的關(guān)係A system curve shows系統(tǒng)曲線顯示出:-the static head component 靜揚(yáng)程( this is constant over the entire capacity range這是一個(gè)不變值)the dynamic head component 動(dòng)揚(yáng)程( which increases with ca

16、pacity流量增加, 動(dòng)揚(yáng)程增加)HeadCapacityStatic headDynamic head流量揚(yáng)程畫上曲線流量揚(yáng)程不同葉輪直徑的性能曲線流量揚(yáng)程效率曲線The best efficiency point (BEP) is the highest efficiency point on the curve 最佳效率點(diǎn)是曲線圖上最高效率的工作點(diǎn)Head CapacityF 200 (8”)F 150 (6”)52%62%56%65%Centrifugal pump curves typically show hydraulic efficiency points離心泵性能曲線圖通常

17、顯示出水力效率PUMP HYDRAULICS ”CENTRIFUGAL PUMP CURVE”水泵水力學(xué) “離心泵性能曲線”Typical Performance Curve水泵性能曲線圖Best Efficiency Point最佳效率點(diǎn)P3P2P1Power Requirements 功率要求ITTPUMP HYDRAULICS“ CENTRIFUGAL PUMP CURVE ”性能曲線圖Head揚(yáng)程 Capacity 流量Pump curves typically show the “absorbed power”(brake horsepower) required to operat

18、e the pump at various points along its Head-Capacity curve水泵性能曲線顯示出在不同工作點(diǎn)上需要操作水泵的軸功率The absorbed power shown on the curve is based on pumping water (specific gravity = 1.0) 曲線圖上的軸功率是基於水來計(jì)算的Q - HF 200 (8”)F 150 (6”)Q - PPower in Kw(bhp軸功率)Power Absorbed Curves軸功率曲線Typical Performance Curve 水泵性能曲線圖電動(dòng)機(jī)功率的決定全曲線不過載工作點(diǎn)軸功率x 1.15首先要知道工作點(diǎn)的軸功率測(cè)試估算(流量(T/h) x 揚(yáng)程(m) / 效率/367 = 軸功率(kw)NPSH氣蝕餘量Head CapacityQ - HQ - NPSHrNPSHr in metres (feet)Pump curves typically show the Net Positive Suction Head Required to op