Abstract: An apparatus for producing and cooling polymer pellets. Hot pellets cut from a die plate extruder are impelled through air and quickly enveloped in a stream of cooling liquid. The stream is then directed to flow in a first horizontal and vertically descending path, and deflected and inverted into one or more succeeding horizontal and vertically descending paths forming a cascade array, until the pellets are cooled to a predetermined temperature.

Abstract: A slide plate filter changer having an upstream seal ring bearing on the filter carrier in the operative position to prevent fluid leakage into the filter carrier channel. The seal ring is subjected to bimodal longitudinal forces respectively produced by screws adjustably bearing on tapered surfaces of the seal ring and the pressure force of the fluid resulting from the difference between the upstream and downstream effective surface areas of the seal ring.

Abstract: A continuous flow filter changer for a fluid having a filter carrier assembly for intermittent sliding transition displacements in a filter channel to align adjacent filters thereon successively with a filter aperture in the flow passage. The duration of each such transition is substantially less than that between transitions. A ring shaped seal sealingly connects between the flow passage upstream thereof and a filter aligned with said aperture to prevent fluid flow except through said filter. The clearance for sliding between the filter carrier assembly and the filter channel is controlled to allow for such displacements while limiting the fluid leakage from the filter channel during a single transition to a predetermined level.