1. Field of the Invention
The present disclosure relates generally to extrusion, and in particular relates to extrusion processing. More particularly, the present invention relates to a system capable of applying and controlling water and vacuum applied to extrudate material.
2. Description of the Prior Art
A typical method for forming parts from plastic utilizes the extrusion method. This method involves a plurality of materials and compounds which are extruded from an extruder. Upon immediately exiting the extruder, the plastic may remain in the molten state. In this state, the molten plastic is easily susceptible to deformation up until it is sufficiently cooled to a solid state.
Accordingly, the molten extrudate must be subject to a strictly controlled atmosphere until it solidifies. There are several methods utilized to minimize the unwanted deformation of the molten extrudate.
While all of these methods minimize unwanted deformations in the molten extrudate, controlling the water itself is an important factor. Water has a mass significant with respect to small extrudate. Any unwanted currents, temperatures, or flows, will have unwanted forces acting on the extrudate. An unwanted flow can push on the wall of thin tube extrudate, resulting in deformation of the desirable circular shape. Flows can also push and pull on the extrudate as the result of forces (eddies). Varying temperatures can change the way extrudate cools, introducing deformations. To further complicate things, rollers may be introduced to prevent hollow extrudate from floating upwards.
Previously, efforts found to control the water flow were minimal. Efforts found included manual attempts to maintain uniform flow. This included simple mechanical valves which were adjusted by an operator. Typically, the valves are completely opened, allowing flow into the tank. This process leaves much to be desired, the control is far from precise, no consideration is given to flow rates or uniformity along the length of the extrudate. Further the process does little to obviate the above mentioned problems present in the prior art.