Method of manufacturing core

Abstract

The method of manufacturing a core of the present disclosure includes the steps of blending dry regenerated sand, wherein the foundry sand utilized in the production of the core is sand regenerated by a dry process, wet regenerated sand, wherein the foundry sand is sand regenerated by a wet process, and new sand in a predetermined ratio, and producing a core from the blended sand. The blending ratio is as follows: dry regenerated sand, 49 wt % to 95 wt %; wet regenerated sand, 1 wt % to 49 wt %; and new sand, 1 wt % to 5 wt %.

What is claimed is: 
     
         1 . A method of manufacturing a core comprising:
 blending dry regenerated sand, wet regenerated sand, and new sand at predetermined ratios, the dry regenerated sand being sand obtained by regenerating, by a dry process, foundry sand used to manufacture a core, the wet regenerated sand being sand obtained by regenerating the foundry sand by a wet process; and   manufacturing a core from the blended sand, wherein   the ratios of the blending are 49 wt % to 95 wt % for the dry regenerated sand, 1 wt % to 49 wt % for the wet regenerated sand, and 1 wt % to 5 wt % for the new sand.   
     
     
         2 . The method of manufacturing a core according to  claim 1 , wherein the ratios of the blending are 69 wt % to 95 wt % for the dry regenerated sand, 1 wt % to 30 wt % for the wet regenerated sand, and 1 wt % to 5 wt % for the new sand. 
     
     
         3 . The method of manufacturing a core according to  claim 2 , wherein the ratios of the blending are 79 wt % to 95 wt % for the dry regenerated sand, 1 wt % to 20 wt % for the wet regenerated sand, and 1 wt % to 5 wt % for the new sand.