PRODUCTION OF ROUND-GRAIN HIGH-QUALITY CRUSHED SAND FOR CONCRETE BY MULTIPLE JAW CRUSHER

摘要

PROBLEM TO BE SOLVED: To obtain round-grain high-quality crushed sand capable of being used in place of sea sand by passing a crushed-stone junk through the inside of a multiple jaw crusher.;SOLUTION: When crushed-stone junk 6 is passed through the inside of a multiple jaw crusher, the larger junk is crushed by a primary crusher 1 and then rounded by the blade of a secondary crusher 2, and the grain is rounded. When the crushed sand leaves a final crusher 5, the corner is abraded, and a round-grain high-quality crushed sand 7 is obtained. When measured by the testing method for 5.8 grain shape determining percentage of absolute volume according to JIS A 5005-1993, the percentage is 51%. The percentage of absolute volume of the crushed stone obtained by crushing the crushed-stone junk is 57%. This value is approximate to 58% which is the percentage of absolute volume of sea sand.;COPYRIGHT: (C)2000,JPO