How to solve these three common problems of slurry pump?

It is a common machine that increases the energy of solid-liquid mixed medium by means of centrifugal force. It is mainly used in mining, metallurgy, construction and other fields. As a common practical auxiliary tool, there are three common problems in the use of slurry pumps, that is, unstable flow, cavitation, and seal failure, which leads to the problem of slurry pump leakage. So how do you solve such problems? Woolen cloth? Let's explore it below!

1. How to solve the unstable flow of slurry pump?

The reasons for the unstable flow of the slurry pump are roughly as follows:

1. The suction pipe or bottom valve is leaking, or the water inlet is blocked, which is a common cause of insufficient flow. It is necessary to check the air leakage source of the suction pipe and the bottom valve and block it in time, or clean up the sludge or blockage at the water inlet.

2. If the voltage is too low, the speed of the slurry pump is reduced, resulting in insufficient flow of the slurry pump. At this time, the power supply voltage should be checked and adjusted in time.

3. There is air leakage in the pipeline or there is air in the pump body. At this time, the air in the pipeline can be discharged in time.

4. Serious wear of the seal ring or impeller will also lead to unstable flow of the slurry pump. The severely worn seal ring and impeller should be checked and replaced in time.

5. The depth of the bottom valve entering the water is insufficient, resulting in air entering during pumping. The depth of the bottom valve should be adjusted according to the suction stroke of the slurry pump.

6. If the slurry pump starts to work normally for a period of time, but then the current gradually decreases, the flow rate is obviously insufficient, and this problem still occurs after restarting the normal operation for a period of time, mostly because the slurry or other debris is accumulating in the suction pipe. Causing cavitation in the slurry pump. In severe cases, there will be loud noise in the slurry pump and the pump head will vibrate significantly. At this time, the front tank and suction pipe should be thoroughly cleaned, and the length below the elbow should be reduced, or a stirring device should be added to reduce Slurry settles.

2. How to solve the cavitation phenomenon of slurry pump?

At a certain temperature, boiling and gasification will occur when the liquid pressure drops below the saturation pressure, which is the characteristic of the liquid itself. At a certain temperature, the saturation pressure is constant and increases with the increase of temperature.

For a centrifugal pump such as a slurry pump, the liquid can be sucked into the pump only by reducing the suction port pressure. When the suction port pressure is lower than the saturated air pressure corresponding to the water temperature, the inhaled liquid will undergo a gasification reaction. The air bubbles formed by gasification gather at the position where the pressure is low in the slurry pump, that is, the back of the blade above the impeller inlet. As the surrounding liquid moves outward, the impact of the liquid will cause noise and vibration. If things go on like this, the impeller will Erosion damage.

Generally speaking, the measures to solve the cavitation phenomenon are as follows:

1. Control the suction liquid surface pressure to prevent the liquid surface pressure from being too low.

2. Control the flow rate of the suction port to make the slurry pump work under the specified beat volume.

3. Properly reduce the installation height of the slurry pump.

4. The suction valve is open enough, and the filter screen should be cleaned frequently.

3. How to solve the failure of the slurry pump seal?

In different operating stages, the reasons for the failure of the slurry pump seal are different. Next, we will analyze them one by one.

1. The slurry pump leaks during the assembly process

The slurry pump is prone to problems during the installation process. Generally, it is necessary to observe whether the slurry pump leaks through a static pressure test. When the leakage amount is small, there is a problem with the dynamic ring or static ring sealing ring in small shifts. If the leakage amount is large, it is There is a problem with the friction pair of the dynamic and static rings. The leaking medium is sprayed along the axial direction, which is mostly the problem of the dynamic ring seal. If the leaking medium is sprayed around or leaks out from the water cooling port, it is mostly a problem with the static ring seal. Adjustment.

2. Leakage during the trial operation of the slurry pump

After the static pressure test, the reason for the leakage of the slurry pump is generally caused by the damage of the friction pair of the dynamic and static rings. There are many reasons for this phenomenon, generally: axial force caused by abnormal phenomena such as cavitation, evacuation, pressure holding, excessive compression when installing the seal, too tight or too loose of the dynamic ring seal ring or static ring seal ring, There are reasons such as particles entering the friction pair in the working medium. The main solution is to reassemble and replace the seal.

3. Sudden leakage during normal operation of the slurry pump

In this case, a few are caused by normal wear or the service life of the slurry pump, but most of them are caused by changes in working conditions or improper operation and maintenance. The main reasons are: pumping cavitation or holding pressure for a long time, the actual output is too small, the sealing cooling water is interrupted, the long-term shutdown and restart without cranking, the increase of corrosive, polymeric or gelling substances in the medium, the slurry The temperature of the working environment of the pump changes drastically, and the working conditions are frequently adjusted. In the process of using the slurry pump, it is necessary to pay attention to the use specifications. Before use, the shaft seal water must be connected, and the pump can be turned off after five minutes of shutdown. When the pump is shut down for a long time, it is necessary to clean the pump cavity and the machine seal with clean water before the shutdown. , Manual cranking when restarting, prolonging the service life of the slurry pump.

Above, we have summarized some common problems in the use of slurry pumps. In order to avoid problems during use, we should standardize the use process of slurry pumps and conduct regular inspections. When abnormal conditions occur, find out the reasons and make timely corrections. Adjustment can ensure the normal use of the equipment and the normal operation of the dressing plant.