According to different foundry plant layouts, technical requirements and molding lines, the sand preparation line layout varies a lot. But it basically includes the following process: used-sand reclamation, used-sand crushing and screening, used-sand cooling, clay and coal powder conveying, new sand conveying and green sand mixing.

1. Used-sand reclamation

The used-sand is collected by sand hopper after sand shakeout, and conveyed to next screening process by vibrating conveyor, rubber belt conveyor and bucket elevator. Scrap iron and iron splashing will be separated by magnetic separating equipments during sand conveying.

2. Used-sand crushing and screening

The used-sand is conveyed into polygonal sieve which can break and screen sand lump of used-sand. The remaining sand lump which cannot be broken will be screened out. At the same time, micro powder is drawn out by induction fan, and qualified used-sand flows down to next process—sand cooling via sieve mesh.

3. Used-sand cooling

Sand cooling equipments like fluidized bed cooler and multi-mix cooler have two mediums air and water basically perform the cooling of used sand. Meanwhile, micro powder is drawn out by induction fan.

4. Clay and coal powder conveying

Clay and coal powder will be conveyed to the material hopper above sand mixer through pneumatic conveyor (Y 95 series low pressure conveyor) and be added to sand mixer in certain ratio by electric scale (Y58 series) accurate weighing.

5. New sand conveying

According to different technical requirements, new sand and used sand can be mixed in predetermined ration before being conveyed to material hopper, or they can be mixed in certain ratio after they are conveyed to material hopper above sand mixer.