All Pumps Machinery Company Limited.

Severe Vibration and Shaft Seal Leakage Analysis of Industrial Slurry Pump

Ⅰ. Serious vibration of industrial slurry pump

Vibration is an inevitable phenomenon that occurs when the equipment is running. It can be divided into different levels according to the severity of the vibration. Equipment vibration that does not exceed the level range is a normal phenomenon. If the equipment has exceeded the normal vibration level, it will directly affect the stable operation of the equipment.

There are many reasons for the serious vibration of industrial slurry pumps, generally there are the following aspects:

1. Impeller eccentric load

The impeller of the slurry pump has undergone a dynamic balance alignment process before leaving the factory, and the quality of each part is relatively uniform, but after a long period of operation, certain wear or adhesion scars will occur, which to a certain extent leads to the rotation of the slurry pump. The eccentric load of the components and the eccentric load after the operation of the slurry pump lead to serious unbalanced rotating force and cause the vibration of the slurry pump.

2. Loose fixing bolts

The industrial slurry pump relies on multiple anchor bolts to connect with the foundation, and at the same time, bolts are also used to maintain the stable state of the pump between various components. Due to the existence of equipment vibration, the long-term operation of the slurry pump will gradually lead to the loosening of these fastening bolts. This will cause the slurry pump to aggravate the vibration due to the loss of the shackles of the fixing bolts. At the same time, the vibration of the equipment, further loosening of the bolts and wear of the components form a vicious circle.

3. The bearing is insufficiently lubricated or the grade of lubricating oil is not up to standard

Good lubrication of equipment can not only reduce the wear of components, but also the oil film formed by the lubricating oil between two parts can absorb a large part of the vibration. While the slurry pump is rotating at high speed, the lubricating oil will form a sufficient oil film between the rolling elements of the bearing to reduce the vibration value.

If the lubrication of the slurry pump is insufficient or the brand of the lubricating oil is not up to standard, the viscosity is insufficient, it is difficult to form an effective lubricating oil film between the bearings, or the lubricating oil film breaks prematurely, it will cause severe vibration of the slurry pump and cause serious wear of the bearings.

Ⅱ. Shaft seal leakage of industrial slurry pump

Shaft seal leakage is the most common failure of slurry. Especially in the petrochemical industry, more than 80% of pump failures come from shaft seal leakage. Therefore, the treatment of shaft seal leakage will determine the utilization rate and maintenance cost of the pump.

In the leakage faults of the shaft seal, more than 65% of the faults are caused by the scaling of the compression spring and the cooling water, which causes the seal end face to be poorly sealed. Therefore, the key to preventing shaft seal leakage is to soften the cooling water of the shaft seal to reduce speed of cooling water scaling.