气冲造型砂型紧实度的实验研究

Experimental Work on Sand Compaction Degree of Air-Impact Molding

采用实验方法研究了砂箱内有模样情况下深凹区砂型湿强度的变化及改进。研究发现在模样的深凹区入口处及模样上表面砂型强度很高，而深凹区入口下方强度最低。深凹比越大，拱效应现象越明显。光洁砂箱壁对减弱拱效应现象有利。

The degree of compaction of molding sand at the deep pocket of a mold and its improvement have been investigated experimentally under plant conditions. It has been found that the degree of compaction of molding sand is higher at the region just above the entrance of the deep pocket,and it is extremely low in the region located at the entrance of the pocket. The larger the Height/Broad ratio is, the more visible this 'arch effects' will be. A clean flask wall will help to reduce the 'arch effects.