Ball mill with external cooling or heating tube - formed by sleeve and successive turns of single helical partition

摘要

Ball mills incorporate a cylindrical grinding chamber with a helicoidal tube on the outer surface for a cooling or heating fluid, the external surface itself forming a wall of the tube. The outer surface of the tube consists of a sleeve coaxial with the wall of the chamber. The lateral boundaries of the tube are formed by the two lateral faces of two successive turns of a single helical partition. The grinding chamber can be heated or cooled over its whole surface by a small flow of circulating fluid, compared to existing ball mills. The construction is simpler and the heat transfer is more uniform. Comparatives tests have shown that under the same conditions and with the same cooling water rate, the temp. in the grinding chamber rose 50 degrees C. in the mill compared to 60 degrees C. in a mill of an existing type.