渣浆泵采用双吸叶轮与单吸的优势
    用两个相互对称的单吸叶轮背旅背的放在一起构成的双吸叶轮，使两个大小相等、方向相反的轴向力相互抵消了。但由于两边密封间隙不完全相同，叶轮不对中等原因，还会产生不大的剩余轴向力，需要由轴承承受。
(2)在两级泵和多级泵中可以采用叶轮对称排列的方式来平衡轴向力
    如图2-54所示，即将两个叶轮或一组叶轮背靠背或面对面的对称安装在一根轴上串联工作。尽管在单个叶轮上仍有轴向力作用，但对整个转子来说，轴向力得到基本平衡，不过由于间隙的影响，还存在有一定的剩余轴向力，需要有推力轴承配合使用。这种方法在单吸两级悬臂泵和蜗壳形多级泵中使用较多。这种方法容积损失很小，但会带来泵的结构较复杂。
(3)平衡孔或平衡管。
    如图2 -55所示，在叶轮后盖板上装一个直径与前盖板密封环直径相等的密封环，同时在叶轮后盖板密封环直径以下处开平衡孔，或加平衡管，使后盖板密封环以下处压力与叶轮

进口处压力相等，这就能平衡大部分的轴向力，剩余的轴向力很小。

平衡孔、平衡管平衡轴向力的方法结构很简单，它的缺点是有一部分液体回流到叶轮入口增加了泵的容积损失，密封环磨损后泄漏量更大，所以密封环磨损后应及时修理更换。同时，从平衡孔回流的液体冲击了叶轮进口的液体，又造成了水力损失，所以泵的效率会略有下降。
(4)平衡盘装置平衡轴向力
    ①平衡盘装置平衡轴向力的工作原理
    平衡盘装置平衡轴向力一般用于节段式多级泵， 如图2-56所示。叶轮轮毂(或轴套)与泵体(或平衡套)之间有一个径向间腺b之外， 在平衡盘与泵体平衡板之间还有一个轴向间隙b。，平衡盘的后面通过平衡管与泵吸入口相通。
    这样，径向间隙前的压力就是未级叶轮背面的压力p，为泵的出口压力。而平衡盘后的压力po为接近泵的入口压力。由于p-Po的压差，液体从叶轮背面流经径向间隙b到平衡盘前，压力下降到p"，然后再流过轴向间院bo到平衡盘的后面，压力下降到Po，最后通过平衡管回流到泵的进口。
    在平衡盘上的两侧，存在着压力差p’-Po;就产生了一个向后的作用力，其方向与叶轮上的轴向力正好相反，这个力就是平衡力。
    当叶轮上的轴向力大于平衡盘上的平衡力时，将泵的转子推向前移动，此时使轴向间隙bg减小，增加了液体流经平衡盘的阻力，因而就减小了泄漏量q。由于泄漏减少，液体流经径向间隙的阻力减小，压力降也就减小，平衡盘前的压力p'就升高了。由于p'的上升，压差p'-po增加，就增加了平衡力。转子不断向前移动，平衡力不断增加，到某一位置时，平衡力和轴向力相等，达到了平衡。同样，当轴向力小于平衡力时，转子将向后移动，移动一定距离后，轴向力和平衡力达到了平衡，
    由于泵在工作中，运行点是经常变化的，轴向力也就经常变化，加上惯性力的作用，转子会经常发生轴向移动，以达到新的平衡，所以平衡盘平衡轴向力是动态的、自动的、完全的平衡轴向力。
    由于用平衡盘平衡轴向力时，转子经常发生轴向移动，所以泵的轴承不能用推力轴承，而是能够轴向移动的轴承。如用滑动轴承，滚动轴承用圆柱滚子轴承、滚针轴承等。如果采用其它滚动轴承不能轴向移动时，需装在一个能轴向滑动的套中，套可轴向移动。由于转子需要自由移动，就不能用在立式多级泵中。
    平衡盘装置平衡轴向力的优点是自动的完全的平衡轴向力，无残余轴向力，但它的缺点是有一定的泄漏量回到泵的进口，增加了泵的容积损失。同时由于平衡盘平衡轴向力时，需要有一个短暂的过程，所以在开泵停泵时会发生平衡盘与平衡板的摩擦，造成平衡盘和平衡板的磨损。尤其是在输送有颗粒的脏的液体时，平衡盘和平衡板磨损更快。当平衡盘和平衡板的平面磨损后，bo间隙关不严，平衡盘不能及时打开，更加速了磨损，形成恶性循环，所以，当平衡盘、平衡板磨损后，应及时给子修理或更换。渣浆泵厂家

Advantages of double suction impeller and single suction in slurry pump

The double suction impeller is composed of two symmetrical single suction impellers which are placed together, so that the two axial forces of the same size and opposite direction cancel each other. However, due to the different sealing clearance between the two sides and the improper impeller, there will be a small residual axial force, which needs to be borne by the bearing.

(2) in two-stage pump and multi-stage pump, the impeller can be arranged symmetrically to balance the axial force

As shown in figure 2-54, two impellers or a group of impellers are symmetrically installed back-to-back or face-to-face on a shaft to work in series. Although there is still axial force on a single impeller, for the whole rotor, the axial force is basically balanced, but due to the influence of clearance, there is still a certain amount of residual axial force, which requires the use of thrust bearing. This method is widely used in single suction two-stage Cantilever Pump and volute multi-stage pump. The volume loss of this method is very small, but the structure of the pump will be more complex.

(3) balance hole or balance pipe.

As shown in figure 2-55, a sealing ring with the diameter equal to that of the front cover plate sealing ring is installed on the rear cover plate of the impeller, and a balance hole is opened below the diameter of the rear cover plate sealing ring of the impeller, or a balance pipe is added to make the pressure below the rear cover plate sealing ring equal to that of the impeller

The pressure at the inlet is equal, which can balance most of the axial force, and the remaining axial force is very small.

The method of balancing the axial force of the balance hole and the balance pipe is very simple. Its disadvantage is that a part of the liquid flows back to the impeller inlet to increase the volume loss of the pump, and the leakage is larger after the seal ring is worn, so the seal ring should be repaired and replaced in time after it is worn. At the same time, the liquid flowing back from the balance hole impacts the liquid at the impeller inlet and causes hydraulic loss, so the efficiency of the pump will be slightly reduced.

(4) balance axial force of balance disk device

① working principle of balancing axial force of balancing disc device

The balance axial force of balance disc device is generally used for segmental multistage pump, as shown in Fig. 2-56. There is an inter radial gland B between the impeller hub (or shaft sleeve) and the pump body (or balance sleeve), and there is an axial clearance B between the balance plate and the pump body balance plate. The back of the balance plate is connected with the pump suction through the balance pipe.

In this way, the pressure before the radial clearance is the pressure P at the back of the impeller, which is the outlet pressure of the pump. The pressure Po behind the balance plate is the inlet pressure close to the pump. Due to the pressure difference of p-po, the liquid flows through the radial clearance B from the back of impeller to the front of balance plate, the pressure drops to P ", then flows through the axial chamber Bo to the back of balance plate, the pressure drops to Po, and finally returns to the inlet of pump through balance pipe.

On both sides of the balance plate, there is a pressure difference p '- Po, which produces a backward force, whose direction is exactly opposite to the axial force on the impeller, which is the balance force.

When the axial force on the impeller is greater than the balance force on the balance plate, the rotor of the pump is pushed forward, which reduces the axial clearance BG, increases the resistance of liquid flowing through the balance plate, and thus reduces the leakage Q. Due to the decrease of leakage, the resistance of liquid flowing through the radial clearance is reduced, the pressure drop is also reduced, and the pressure P 'in front of the balance plate is increased. As p 'rises, the pressure difference p' - Po increases, which increases the equilibrium force. The rotor moves forward continuously, and the balance force increases continuously. When it reaches a certain position, the balance force and the axial force are equal, and the balance is achieved. Similarly, when the axial force is less than the balance force, the rotor will move backward. After moving a certain distance, the axial force and balance force are balanced,

Since the operation point of the pump often changes, and the axial force often changes. In addition to the inertia force, the rotor will often move axially to achieve a new balance, so the balance axial force of the balance disk is dynamic, automatic and complete.

When balancing the axial force with the balance disk, the rotor often moves axially, so the pump bearing can not use the thrust bearing, but can move axially. Such as the use of sliding bearings, rolling bearings with cylindrical roller bearings, needle bearings, etc. If other rolling bearings cannot move axially, they shall be installed in a sleeve that can slide axially, and the sleeve can move axially. Because the rotor needs to move freely, it can not be used in vertical multistage pump.

The advantage of balancing axial force of balancing disc device is that it can balance axial force automatically and completely without residual axial force, but its disadvantage is that there is a certain amount of leakage back to the inlet of the pump, which increases the volume loss of the pump. At the same time, the balance plate needs a short process to balance the axial force, so the friction between the balance plate and the balance plate will occur when the pump is started and stopped, resulting in the wear of the balance plate and the balance plate. Especially when transporting dirty liquid with particles, the balance plate and balance plate wear faster. When the plane of balance plate and balance plate is worn, Bo gap is not closed tightly, balance plate cannot be opened in time, which accelerates wear and forms a vicious cycle. Therefore, when balance plate and balance plate are worn, repair or replace them in time. Slurry pump manufacturer