Circulating pump wear

Circulating pump wear is mainly caused by cavitation.

Cavitation is a fluid dynamic phenomenon, which is mainly caused by the change of internal flow pressure. When the flow rate in a local area of the pump increases and the pressure drops to the bottom gasification pressure, the gasification of water will produce a large number of bubbles.

When these bubbles enter areas of high water pressure, they are rapidly compressed and burst, creating a powerful force (up to several hundred atmospheres) that repeatedly strikes the pump casing and rotor blades. The bubbles that seep into the water also contain a certain amount of gas that can cause certain amount of oxidation inside the turbine.

When the bubbles continue to burst caused by the repeated impact of more than the strength of the pump material is the parts will produce erosion, surface pitting, and even holes. Cavitation corrosion can cause unstable pump operation, large vibration and other unsafe factors.

Repair process

I. surface treatment:

1. Rinse the inside of the equipment with high pressure water gun

2. Degreasing and dehumidification: adjust the flame to 10CM long with oxygen acetylene and make the flame bake the surface of the workpiece repeatedly and evenly at the speed of 5cm/min to remove the grease and moisture on the surface of the workpiece;

3. Sandblasting and derusting: remove the oxide layer on the surface of the workpiece, and visually check that the sandblasting surface can show the uniform metal color. After sandblasting, the workpiece is not allowed to directly contact the sandblasting surface with grease gloves. After sandblasting, the workpiece should pay attention to moisture. Cover areas that do not need to be treated.

Ii. Selection of wear-resistant and anticorrosive materials:

1. Npt-c-14 wear resistant material

Two-component, metal carbide as the composite material, abrasion resistance is 1-3 times of medium carbon steel, high compressive strength, good impact resistance. Used for repair and large area preprocessing of over-flow parts with particle size below 5-8mm. Effectively protect and repair pump, fan, flue and other surface wear and corrosion.

2. Npt-c-16-30 wear resistant material:

Two-component, metal carbide as the composite material, abrasion resistance is 1-3 times of medium carbon steel, high compressive strength, good impact resistance. Used for repairing over flow parts with particle size less than 3mm and large area preprocessing, such as flotation tank, stirring bucket, blade, etc.

3. Npt-c-100 wear resistant material

The two-component composite material with metal carbide as the aggregate has 1-3 times the relative wear resistance of medium carbon steel, high pressure resistance and good impact resistance. Used for surface smoothness repair and large area precoating.