Barge Unloader - St. Croix River, Minnesota

The tower, located in the river, supports a vertical lift bridge containing a bucket digging wheel. The barge is towed into place and the digging wheel lowered into place. The digging wheel is activated and proceeds to unload coal from the barge at the rate of 5000 tph. Specially designed hydraulic scraper arms are then utilized to clear the forward and rear hold of the barge that are not accessible by the digging wheel. Unique features include integration of mechanical aspects of operation with structural support requirements. Also, the structural calculations considered many loading conditions required to account for variability of loads due to location of bridge travel, bucket wheel traverse and operation of the hydraulic arms.

The Schaffer Engineering Company Bernard Schaffer, P.E., President 40 Crane Circle · New Providence, NJ 07974 (908) 464-1692 · Fax (908) 464-3655; BSengineer@comcast.net