【正文】 ogress alternately, and the piston can39。t be in field change ceaseless in displacement process middle , whose speed among. In the pump only having a cavity working, not only the pump microtime rate of flow vary with with time, and be discontinuous. With job cavity increasing by, microtime rate of flow pulsation extent is more and more small, and even pragmatic upper not bad regard as to stabilize a stream.Average rate of flow is constantTheoretically, the pump rate of flow depends on main pump structure physics , chemical property independences such as parameter n (every minute intercourse number of times) , S (piston travel) , D (piston diameter) , Z (piston number) , the temperature , viscosity with the independence discharging pressure, and with transporting medium only. Therefore saying a pump39。s, rate of flow is constant.The pump pressure depends on pipeline characteristic propertyUnable pressure been to depend on a pump unit because the pump sets a limit for per se, pipeline characteristic property, has nothing to do with rate of flow pump snapout moving back and forth moreover. Just say, if thinking that transporting liquid is inpressible,in terms of theory think that pump moving back and forth39。s discharge pressure will not accept any restricting , be OK to discharge pressure according to the pump unit pipeline characteristic property , the what any needs building a pump. The capital of pump moving back and forth natural , all the regulation discharging pressure39。s having a pump , this is not that pressure can not rise again, but say only because of prime mover fixed power and the pump saying the snapout that a pump self structure intensity restricting, do not allow being put into use under exceeding this once discharging pressure but self own.Have stronger adaptability to transporting mediumThe pump moving back and forth can transport any medium , physics function and chemistry function restricting hardly accepting medium in principle. Certainly, since hydraulic whole course of restricts as well as material and the manufacturing engineering sealing off a technology39。s, also may e across the condition being able to not fit in with sometimes.Have fine self attracts a function.The pump moving back and forth has fine sucking in not only function, and there are still fine self attracts a function. Have no need of irrigation pump therefore , to the pump moving back and forth most, generally before starting.Machine efficiency height , energy conservation.Highhanded intercourse pump rate of flowThe pump theory rate of flow: Qt = AsnZStyle is hit by Qt pump theory rate of flow。 A bar piston (or section of piston) area。 S route or distance of travel。 The n crank shaft rotation rate (or the bar piston every minute intercourse number of times) Z unites a number (bar piston or piston number)Actual pump rate of flow: Q = Qt－Q.Style is hit by Q pump rate of flow。 Qt pump theory rate of flow。 The pump rate of flow loses Q.The factor that the rate of flow bringing about a pump loses has: The volume bringing about since liquid presses or expands is lost。 The volume bringing about since the valve lags when being closed down is lost。 Since the valve closes the day afer tomorrow do not lose strictly, by sealing off the volume that leakage soft and floury brings about。 The volume by the fact that the bar piston , piston rod or the piston ring leakage bring about is lost.The pump microtime rate of flowSingle cylinder Shan effect pump rate of flow curve: Three jar Shan effects pumps rate of flow is the single cylinder Shan effect pump rate of flow overlying on three phasesWhose curve as follows: The pump powerThe pump effective power: The energy that the inner , the liquid being discharged by the pump gain time the unit from the pump is called an effective power.Ne＝PQ In style, the Ne effective power , P satisfy pressure , Q rate of flowUnit queen formula bees substitution:Ne(KW)＝1/P(Kgf/cm2)Q(m3/h)。The power thinking that the temperature rises to actuator efficiency , machinery friction , volumetric efficiency , medium waiting for cause to bring about loses , chooses the pump moving back and forth when prime mover power, to low pressure, N＝1/(~)N；To highhanded the pump moving back and forth , N = 1/ ( ~ ) N.The pump application range moving back and forthThe pump moving back and forth applies to highhanded small rate of flow mainly , requires that the pump rate of flow is constant or the quantify , proportionality transport various different medium , demands occasion to suck a function in well, or demands to there is self attracting a function39。s or. Under in the nowadays world sources of energy is shortsupplied circumstances, the pump moving back and forth is the energy conservation product, the mine has exploited , petroleum has got in a lot of industry such as fine chemicals , food medicines and chemical reagents treating broad usage in the sources of energy. This kind of pump structure is paratively plicated , forming a plete set is strong but General Availability is bad, the breed is many but batches are small.中文翻譯高壓往復泵的特點高壓往復泵的使用壓力一般應在10MPa～100MPa之間。它屬于容積式泵，借助工作腔里的容積周期性變化來達到輸送液體的目的；原動機的機械能經泵直接轉化為輸送液體的壓力能；泵的容量只取決于工作腔容積變化值及其在單位時間內的變化次數，理論上與排出壓力無關。往復泵是借助于活塞在液缸工作腔內的往復運動（或通過隔膜、波紋管等撓性元件在工作腔內的周期性彈性變形）來使工作腔容積產生周期性變化的。在結構上，往復泵的工作腔是借助密封裝置與外界隔開，通過泵閥（吸入閥和排出閥）與管路溝通或閉合。其特點歸納如下： 瞬時流量是脈動的這是因為在往復泵中，液體介質的吸入和排出過程是交替進行的，而且活塞在位移過程中，其速度又在不斷地變化之中。在只有一個工作腔的泵中，泵的瞬時流量不僅隨時間而變化，而且是不連續(xù)的。隨著工作腔的增多，瞬時流量的脈動幅度越來越小，乃至在實用上可以認為是穩(wěn)定流。 平均流量是恒定的理論上，泵的流量只取決于泵的主要結構參數　　n（每分鐘往復次數）、S（活塞行程）、D（活塞直徑）、Z（活塞數目），與排出壓力無關，且與輸送介質的溫度、粘度等物理、化學性質無關。所以說泵的流量是恒定的。泵的壓力取決于管道特性往復泵的排出壓力不能由泵本身限定，而是取決于泵裝置的管道特性，并且與流量無關。也就是說，如果認為輸送液體是不可壓縮的，那么，在理論上可認為往復泵的排出壓力將不受任何限制，即可根據泵裝置的管道特性，建立泵的任何所需的排出壓力。當然，所有往復泵都有一個泵的排出壓力的規(guī)定，這不是說該泵的排出壓力不會再升高，而只是說，由于原動機額定功率和泵本身的結構強度的限制，不允許在超出這一排出壓力下使用而己。