Abstract: A mixing device is provided having spaced end frames and side walls defining an internal mixing chamber and a removable hopper affixed thereto for receiving material to be fed into the chamber. A weight extends into the hopper and the chamber to force the material through the hopper and into the mixing chamber. A sleeve is provided to protect the internal portion of the mixer within the end frames from abrasion due to sidewise motion of the weight during mixing and extend upward into the hopper to inhibit relative motion between the hopper and the mixer frames and side walls during the mixing process.

Abstract: Four hydraulic cylinders are mounted on support segments at approximately 90.degree. intervals about the sealing gland ring of an internal rotary mixer. The piston rods of the hydraulic cylinders directly engage the gland ring and the cylinders are supplied by a static hydraulic system. The hydraulic system supplies a pair of cylinder assemblies on either end of the rotor shaft thereby providing a continuously balanced force to the gland rings.