Abstract: A heater-cooler system includes a plurality of heaters in thermal communication with a barrel of an extruder. The heater-cooler system includes a plurality of shroud assemblies that each define a cavity between a shroud assemblies and one of the heaters. Each heater is enclosed by one of the shroud assemblies. Each of the shroud assemblies has an intake port and an exhaust port. The heater-cooler system includes a blower connected to the intake port. The blower delivers air to the cavity. A portion of the each of the shroud assemblies at the exhaust port defines a flap moveably integrated therewith. The flap is opened by an increase in pressure in the cavity caused by operation of the blower. The flap seals the cavity in a closed position upon termination of blower operation. The flap is configured as a poppet valve.

Abstract: This invention relates to the field of multiple layer plastic extrusion, and more particularly to assemblies in which thin or micro-layers of polymer material are formed which polymer material may be from two or more individual extruders, and delivered to a multilayer combining adapter in association with an extruder die or other utilizations. The combining adapter of this invention is referred to herein as a flow velocity profiler (FVP) and includes a cartridge assembly body that is formed with individual cavities that receive one of a plurality of individual precision layering inserts. Changing individual inserts is less time intensive than changing an entire body as required in prior art.

Abstract: A plastic resin pelletizer system for controlling the position of the pellet cutting knife blades in relation to a die plate face includes vibration detection pick-up in the form of a piezoelectric accelerometer mounted to the pelletizer die plate. Characteristic frequencies or a signature output is identified as representing the condition of contact between the blades and the die face, and the amplitude of the characteristic signature is used to indicate the extent or degree of pressure of the contact, in controlling the position of the knives with respect to the die plate.