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渣漿泵的串聯怎么工作
一、使用場合
    泵的串聯工作就是將第一臺泵的出口與第一臺泵的入口相連接，以增加揚程。常用于以下場合:
    (1)單臺泵的揚程不能滿足裝置壓力的需要時;

(2)同時要增加流量和壓力;

(3) 管路長距離輸送;

(4)改善后面一臺泵的汽蝕性能。

二、兩臺同性能泵串聯工作

圖4-2所示為相同性能泵串聯工作的運行曲線圖，曲線I、II為兩臺泵的性能曲線，曲線I+II為串聯工作時的性能曲線，它是將單獨泵的性能曲線在同一流量下把楊程迭加起來得到的。與裝置揚程特性曲線III相交于M點，M點即為串聯工作時的工作點。此時流量為Qm，揚程為Hm。
    串聯后每臺泵的運行工況點可以從M點作縱坐標的平行線交曲線I、II于B點，即為串聯后的每臺泵工作點。在B點的流量為Q1 =QII，揚程為H ,Hm。顯然串聯工作的特點是流量彼此相等，即Qm = Q1=Qm,總揚程為每臺揚程的總和，即HM = Hq +Hm。
    串聯前每臺泵的工作點為C點( Qc、He、Pc、ηc )，與串聯后的工作點B點參數相比較:
                           QM = Q1=QII> Qc
                             Hc<Hm<2Hc

(4)由于外界負荷變化很大，需要用泵的臺數來進行調節;

(5)減小備用泵的容量。

二、兩臺同性能泵并聯工作

圖4-4為兩臺同性能泵的并聯工作時的性能曲線。圖中曲線I、II為兩臺同性能泵的性能曲線，并聯工作時的性能曲線為I+II，III為裝置揚程特性曲線。
    并聯工作曲線I+II的畫法是將泵單獨的性能曲線在揚程相等的條件下把流量迭加而成，它與裝置揚程特性曲線皿相交于M點，即為并聯工作時的工作點，此時流量為Qm，揚程為HM。
    確定單個泵的工況，可由M點作橫坐標的平行線與單臺泵性能曲線交于B點，即為每臺泵并聯工作時的單獨工作點，此時B點流量Qg=Q1 =Qπ，B點的揚程Hn=Hq =Hye并聯工作的特點是:兩臺泵的揚程相等，即Hx=Hp=Hq =Hπ,總流量為兩臺泵之和，即Qx=Qr +Qn =2Qb  

未并聯前每臺泵單獨工作時的工作點為C (Qe、H、Pc、7。)，并聯后每臺泵的工作點(Q、H。、Pr、7n).比較并聯前每臺泵的參數和并聯后每臺泵的參數，可以看出:
                               Qb<Qc<QM<2Qc  
                                 Qm = 2Qb

Hb=Hm> Hc

這說明兩臺泵并聯工作時的流量Qm等于并聯運行時各臺泵的流量之和，和并聯前一臺泵單獨工作時相比，兩臺泵并聯后的總流量QM小于一臺泵單獨工作時流量的2倍，而大于一臺泵單獨工作時的流量Qc。并聯后單臺泵工作的流量Qu比并聯前單臺泵工作的流量Qc小，而揚程比并聯前單臺泵工作時高些，這是因為管道摩擦損失隨流量的增加而增大了，就需要提高泵的揚程來克服增加的損失，故Hb> Hc，因而流量就相應減少了。  渣漿泵廠家

How to operate the slurry pump in series

I. use occasion

The series work of the pump is to connect the outlet of the first pump with the inlet of the first pump to increase the lift. Commonly used in the following situations:

(1) when the head of a single pump cannot meet the pressure requirements of the device;

(2) increase flow and pressure at the same time;

(3) long distance pipeline transportation;

(4) improve the cavitation performance of the latter pump.

Two pumps of the same energy operate in series

Figure 4-2 shows the operation curve of the same performance pump in series, curve I and curve II are the performance curves of two pumps, curve I + curve II are the performance curves of the two pumps in series, it is obtained by superposing the performance curves of individual pumps under the same flow. It intersects with the head characteristic curve III of the device at point m, which is the working point in series operation. At this time, the flow is QM and the lift is HM.

After series connection, the operating point of each pump can be from point m as the vertical coordinate of the parallel line intersection curve I and II to point B, that is, the operating point of each pump after series connection. The flow at point B is Q1 = QII, and the lift is h, HM. Obviously, the characteristic of series operation is that the flow is equal to each other, that is, QM = Q1 = QM, and the total head is the sum of each head, that is, HM = HQ + HM.

The working point of each pump before series connection is point C (QC, he, PC, η C), compared with the parameter of point B after series connection:

QM = Q1=QII> Qc

Hc<Hm<2Hc

(4) due to the great change of external load, the number of pumps shall be used for adjustment;

(5) reduce the capacity of standby pump.

Two pumps of the same energy operate in parallel

Figure 4-4 shows the performance curve of two pumps in parallel. The curves I and II in the figure are the performance curves of two same-sex energy pumps. The performance curves of parallel operation are I + II and III are the head characteristic curves of the device.

The drawing method of parallel working curve I + II is that the flow is superposed by the separate performance curve of the pump under the condition that the head is equal. It intersects with the head characteristic curve plate of the device at point m, that is, the working point in parallel working, at this time, the flow is QM and the head is HM.

To determine the working condition of a single pump, the parallel line with the abscissa of point m and the performance curve of a single pump can be intersected at point B, that is, the single working point of each pump in parallel operation. At this time, the flow of point B QG = Q1 = q π, and the lift of point B HN = HQ = hye in parallel operation are characterized by: the lift of two pumps is equal, that is, HX = HP = HQ = h π, and the total flow is the sum of two pumps, that is, QX = QR + QN = 2qb

Before parallel connection, the working point of each pump is C (QE, h, PC, 7). ）, working points (Q, H) of each pump after parallel connection. , PR, 7n). Comparing the parameters of each pump before and after parallel connection, we can see that:

Qb<Qc<QM<2Qc

Qm = 2Qb

Hb=Hm> Hc

This shows that the flow QM of two pumps in parallel operation is equal to the sum of the flow of each pump in parallel operation. Compared with the previous pump in parallel operation, the total flow QM of two pumps in parallel operation is less than 2 times of the flow of one pump in separate operation, and greater than the flow QC of one pump in separate operation. After parallel connection, the flow Qu of single pump is smaller than that of single pump before parallel connection, while the lift is higher than that of single pump before parallel connection. This is because the friction loss of pipeline increases with the increase of flow, so it is necessary to increase the lift of pump to overcome the increased loss, so HB > HC, so the flow is correspondingly reduced Slurry pump manufacturer