Method for cleaning the surface of lost foam castings

Eliminate sticky sand on the inner and outer surfaces of lost foam castings; cover the seams, burrs, and riser laser cutting marks on the clinical diagnostic surfaces and core heads. The way is as follows:

1. Manual cleaning: suitable for spare parts, small batch production, and parts with complicated shapes;

2. Drum cleaning: general cleaning of lost foam product Drums are a commonly used cleaning machine. The basic working principle of sand-foundry iron castings is to use the friction and impact between the casting and the extra-angle steel to remove the sticky sand, burrs, and scale on the surface of the casting. The structure of the machine is simple and easy to manufacture, and the cleaning effect is very good; the disadvantage is that the production efficiency is low, the noise is large, and it is suitable for large, medium, and small rolling mills.

3. Shot blasting and derusting treatment equipment: It uses compressed gas as the driving force to quickly spray iron shots onto the castings to be removed and uses the impact force of the iron shots to remove sand and scale on the surface of the castings.

Raw sand selection criteria are as follows:

1. The strength is suitable for castings of submerged slurry pumps. Too much or too little strength in high-quality ductile iron is bad. Too much strength in high-quality gray cast iron will cause the casting to shrink and cause casting cracks; if it is resistant to If the compressive strength is too low, it is easy to collapse, and the swelling of the sand will cause defects. In obvious cases, castings will be discarded.

2. Good air permeability, reducing the generation of vent holes Vents are very dangerous. If there is an air hole in the grommet of the submerged slurry pump, its service life will be doubled.

3. Good flame retardancy; if the flame retardancy is too low, it will cause sand to stick in castings.

4. Good granularity; otherwise, it will seriously affect the surface quality of castings. Casting is the whole process of pouring molten metal material into mold shells.