| 摘要 |
<p>A balling drum which includes a conventional end discharge preferably of the type shown by U. S. Pat. No. 2,822,076, granted to John F. Baier on Feb. 4, 1958, and which balling drum additionally includes a discharge section intermediate the length of the drum and upstream of the end discharge section, the intermediate discharge section comprising helically extending port means in the form of helical slots through the wall of the drum which slots are so positioned with respect to the angular path of load material flow relative to the internal surface of the balling drum that some predetermined percentage of the entire load passing through the balling drum, preferably about 50 percent of the entire load, is discharged by the intermediate discharge section, the helical slots substantially evenly distributing the discharge flow from the intermediate discharge section onto a classifying screen positioned beneath the intermediate discharge section.</p> |
