The axial balance of an ordinary multistage centrifugal pump is performed by a balancing disk device, so the balancing disk and balancing ring play a significant role in a multistage centrifugal pump. The stability of the balancing disk of a multistage centrifugal pump is related to the normal operation and use of the multistage pump. The structure of the balance disk device for mining multistage centrifugal pumps consists of a balance disk, a balance seat, and an adjustment sleeve (some balance disks and adjustment sleeves are integrated).
In the operation of multistage centrifugal pumps, the working principle of the balancing disc device is: the pressurized liquid coming out of the final stage impeller flows into the water chamber between the balancing disc and the balancing seat through the radial gap between the balancing seat and the adjusting sleeve, leaving the water chamber in a high-pressure state. A balance pipe is connected to the inlet of the pump behind the balance plate, and its pressure is approximately the inlet pressure of the pump. In this way, the pressure on both sides of the balance plate is not equal, resulting in a backward axial balance force. The magnitude of the axial balance force varies with the change in axial displacement and the adjustment of the axial clearance between the balance disk and the balance seat (i.e., the change in the pressure of the water chamber between the balance disk and the balance seat), thereby achieving the goal of balance. But this balance is often dynamic.
In the operation of multistage centrifugal pumps, the balance plate of the multistage pump is easily damaged. Once the balance disc of the multistage centrifugal pump is damaged, the balance ring of the multistage centrifugal pump will lose its balance function, and the increase in the number of multistage centrifugal pumps will exacerbate the wear of the impeller of the multistage centrifugal pump.
Generally, the balance plate of a multistage centrifugal pump is damaged. The following aspects are mainly inspected to damage the balance of the rotor part of the multistage centrifugal pump, resulting in wear of the balance ring and balance plate.
1. Whether the flow of multistage centrifugal pump exceeds the rated flow too much;
2. Check whether the balancing water pipe of the multi-stage centrifugal pump is blocked,
3. Whether the diameter of balancing water pipe of multistage centrifugal pump is too small;
4. Check whether there is water channeling on the contact surface between the balance ring and the outlet section of the multistage centrifugal pump.
Therefore, when there is a fault in the balance disk, please timely check these aspects and timely eliminate the fault.