Material selection of overflow parts of slurry pump

2023-09-25

Slurry pumps are mainly used to transport solid-liquid mixtures containing hard particles, and are widely used in coal, metallurgy, mining, thermal power, chemical, water conservancy and other industries. The delivered solid-liquid mixture presents irregular movement in the high-speed rotating impeller. The overflow parts of the pump are subjected to strong wear under the working conditions of this "liquid grinding wheel", and also bear the corrosion of the medium, resulting in the overflow parts. The life span is shortened. Therefore, the design of the slurry pump is fundamentally different from the design of the water pump. The design of clean water pump mainly pursues efficiency and cavitation index, while slurry pump should pay attention to cavitation, wear resistance and corrosion resistance while pursuing efficiency.

There are many factors involved in the wear of the overflow parts of the slurry pump, and the wear mechanism varies from part to part, but in general it can be divided into three categories.

1. Erosion wear

During the operation of the slurry pump, the solid particles carried in the liquid impact the surface of the overflow part at a certain speed, causing material loss. According to the wear surface analysis of the failed parts, the erosion wear mechanism can be divided into cutting wear, deformation fatigue wear and cutting deformation composite wear.

2. Cavitation damage

In the operation of the pump, the local area of its overflow part, for some reason, the absolute pressure of the pumped liquid drops to the vaporization pressure at the temperature at that time, and the liquid will start to vaporize at this position, generating steam and forming bubbles. These bubbles move forward with the liquid, reaching a high pressure, and the bubbles collapse sharply. While the bubbles condense, the liquid block fills the voids at high speed and strongly impacts the metal surface. The metal surface is fatigued by this impact and spalling, resulting in material loss, and in severe cases, the metal surface is honeycomb.

3, corrosion

When the conveying medium has a certain acidity and alkalinity, the overflow parts of the slurry pump will also be corroded and worn, that is, the material loss under the joint action of corrosion and wear.

Key words:

Jinrun pum

Slurry pump maintenance skills

None

Related News