Abstract: A die changing mechanism for use with a vertical-axis extrusion apparatus that includes a die housing and an extrusion die section, such as an inner section that is secured to the housing by a threaded connection. The apparatus includes a transportable support assembly and a breaker assembly supported by the support assembly and adapted to be positioned in an initial position in rotationally interlocking engagement with the inner die section. The breaker assembly is connected to the support assembly by threaded means, and is adapted for rotational movement relative to the support assembly about a vertical axis corresponding to the screw axis. The pitch of the threads of the threaded means is the same as the pitch of the threads by which the die section is connected to the die housing.

Abstract: An accumulator tank for pressurizing and supplying liquid to a system comprises a pressure vessel having a wall defining a closed pressure chamber. The pressure vessel is provided with an internal flexible air cell which divides the pressure chamber into first and second variable volume compartments containing pressurized air and water, respectively. Perforated conduits are provided in the second compartment in fluid communication with a port, and extend between the wall of the pressure vessel and the flexible air cell. The perforated conduits provide fluid communication between the port and portions of the second compartment when the air cell seals against the wall to otherwise isolate those portions of the second compartment in fluid communication with the perforated conduits.