Rounding and smoothing process for hewn stone block

摘要

The process involves feeding stones through a drum (1). The drum rotates causing the stones to roll and tumble over and wear against one another. The stones can be passed through the drum many times and be screened and sprayed with water to remove debris. The drum has an inner diameter (D), which is several times greater than the dimensions of the blocks. Longitudinal U-shaped channels (2) are attached by their webs to the inside wall of the drum and the longitudinal axis of the drum slopes slightly. Elastomeric sheet (4) covered steel plates (3) at an angle to the drum sides are attached to one side of each channel and set the stones tumbling.