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渣漿泵的分類
離心泵的類型很多,分類方法也很多,通?？砂聪铝蟹椒ǚ诸?。

1.按液體吸入葉輪的方法分類

(1)單吸式(圖1- 1),葉輪只一側有吸入口。

(2)雙吸式(圖1-2),葉輪兩側都有吸入口，常用于流量較大的情況，軸上承受的軸向推力由于左右對稱，可以基本平衡。
2.按葉輪級數分類
    (1)單級泵(圖1-1.圖1-2)，泵體中只裝有1個葉輪。
    (2)多級泵(圖1 3.圖 14).同 一根系軸 上串裝2個以上葉輪，以產生較高的能頭。
3.按殼體剖分方式分類

(1)中開式泵(圖1- 2),殼體按通過泵軸中心線的水平面剖分。

(2)分段式泵(圖1- 4) ,殼體按與軸垂直的徑向平面剖分。
此外，還可按泵軸在空間的方位分為臥式泵和立式泵;按輸送介質不同又可分為水泵、油泵雜質泵及耐腐蝕泵 等。
三、離心泵的性能參數
1.流量

泵單位時間內排出的液體量稱為泵的流量,體積流量用Q表示，單位是m3/s;質量流量用G表示，單位為kg/s。 二者的關系為:
                              G=pQ                                    (1-1)

式中ρ——液體密度，kg/m3。

揚程

揚程是指單位質量或單位重量的液體經過泵后的機械能增加值，即從泵中獲得的有效能量，常用符號H表示，單位為J/kg (單位質量)，或J/N(單位重量)。對J/N進行量綱簡化，J/N=N·m/N=m，可以用m來表達。在工程實際中常用m,雖然這一單位與高度單位一致，都是m，但不應把泵的揚程簡單理解為輸送液體達到的高度，因為泵的揚程不僅用來提高液體的位能，還用來克服液體在輸送過程中的流動阻力以及提高液體的靜壓能和速度能等。

根據揚程定義，液體在泵入口與泵出口之間獲得的能量增加值，可按伯努利方程表述為:

由于泵進、出口截面積和高度相差不大，因此進、出口截面的速度能差和高度差均不大，所以泵的揚程主要是增加液體壓力。
3.轉速
    轉速是指泵軸單位時間旋轉的次數，用n來表示，常用單位為r/min。它是影響泵性能的一個重要參數。當轉速變化時，泵的流量、揚程、功率等參數都要發生變化。
4.功率
    在離心泵中，因為有機械摩擦、流動損失和容積損失，導致功率在由驅動機通過泵軸和葉輪傳遞給液體的過程中不斷減小，因此各處功率的表達式不同，具體表達如下。
1)軸功率
    離心泵的軸功率是由驅動機傳遞到泵主軸上的功率，也稱泵的輸入功率，用P來表示。
2)有效功率 渣漿泵

離心泵的有效功率是指單位時間內泵出口流出的液體從泵中獲得的能量也稱輸出功率，用Pe來表示，其公式為

Classification of slurry pumps

There are many types of centrifugal pumps, and there are many classification methods. Generally, they can be classified according to the following methods.

1. Classification according to the method of liquid suction impeller

(1) Single suction type (Figure 1-1), only one side of impeller has suction port.

(2) Double suction type (Figure 1-2), both sides of the impeller have suction ports, which are commonly used in the case of large flow. The axial thrust on the shaft can be basically balanced due to the symmetry of left and right.

2. Classification by impeller stages

(1) Single stage pump (Fig. 1-1. Fig. 1-2), only one impeller is installed in the pump body.

(2) Multistage pump (FIG. 13, FIG. 14). More than two impellers are installed in series on the same root axis to produce higher energy head.

3. Classification according to the division method of shell

(1) Split pump (Fig. 1-2), the shell is divided by the horizontal plane passing through the center line of the pump shaft.

(2) Segmented pump (Figure 1-4), the shell is divided according to the radial plane perpendicular to the shaft.

In addition, it can also be divided into horizontal pump and vertical pump according to the orientation of the pump shaft in the space; it can also be divided into water pump, oil pump impurity pump and corrosion-resistant pump according to the different transmission medium.

3、 Performance parameters of centrifugal pump

1. traffic

The liquid discharged in unit time of the pump is called the flow of the pump, the volume flow is expressed in Q, and the unit is m3 / S; the mass flow is expressed in G, and the unit is kg / s. The relationship between them is as follows:

G=pQ                                    (1-1)

Where ρ - liquid density, kg / m3.

lift

Head refers to the added value of mechanical energy per unit mass or per unit weight of liquid after passing through the pump, that is, the effective energy obtained from the pump, commonly expressed by the symbol h, in J / kg (unit mass), or J / N (unit weight). The dimension of J / N is simplified. J / N = n · M / N = m, which can be expressed by M. M is commonly used in engineering practice. Although this unit is the same as the height unit, it is m, but the head of the pump should not be simply understood as the height of the liquid delivered, because the head of the pump is not only used to improve the potential energy of the liquid, but also to overcome the flow resistance of the liquid in the process of delivery and improve the static pressure energy and speed energy of the liquid.

According to the definition of head, the energy increment value of liquid between pump inlet and pump outlet can be expressed as follows according to Bernoulli equation:

Because the cross-sectional area and height of the inlet and outlet of the pump have little difference, the speed energy difference and height difference of the inlet and outlet cross-section are not big, so the lift of the pump is mainly to increase the liquid pressure.

3. speed

Rotation speed refers to the number of times the pump shaft rotates per unit time, which is expressed in N, and the common unit is R / min. It is an important parameter that affects the performance of pump. When the speed changes, the flow, head, power and other parameters of the pump will change.

4. power

In the centrifugal pump, because of the mechanical friction, flow loss and volume loss, the power is continuously reduced in the process of being transmitted to the liquid by the driving machine through the pump shaft and impeller. Therefore, the expressions of the power are different. The specific expressions are as follows.

1) shaft power

The shaft power of centrifugal pump is the power transmitted from the driver to the main shaft of the pump, also known as the input power of the pump, expressed by P.

2) Effective power slurry pump

The effective power of centrifugal pump refers to the energy obtained from the pump by the liquid flowing out of the pump outlet in unit time, also known as the output power, which is expressed by PE, and its formula is