▎ 摘　　要

NOVELTY - Runner tube comprises 70-80 wt.% of waste paper pulp, 5-8 wt.% of corundum powder, 6-12 wt.% of bauxite powder, 2-5 wt.% of clay, 1-3 wt.% of water glass, 0.02-0.05 wt.% of graphene, 0.5-1 wt.% of sodium hexametaphosphate and the rest is fused magnesia fine powder. USE - Runner tube used for casting. ADVANTAGE - The runner tube is simple, cost effective in manner. It has good durability and has improved production efficiency. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method for preparing runner tube for casting, which involves : (A) putting waste paper and water into waste paper pulp to adjust the concentration of the paper to 3-5%; (B) mixing corundum powder, bauxite powder, clay, water glass and half of the amount of sodium hexametaphosphate to obtain slurry; (C) stirring; (D) putting obtained slurry in molding machine; (E) mixing graphene, fused magnesia fine powder and the remaining sodium hexametaphosphate to obtain mixture; (F) grinding; (G) sieving to 250 mesh to obtain fire-resistant surface coating; and (H) heating obtained fire-resistant surface coating to obtain runner tube.