Melt pump seal with vacuum housing

摘要

A method and apparatus for preventing fluid leakage through a sealing mechanism of a melt pump into a vessel during the period of establishing a vacuum therein and increasing the viscosity of the material fed thereto. The method includes enclosing in a fluid-tight relationship the area of fluid leakage adjacent the sealing mechanism and reducing the pressure in the enclosed area sufficiently to prevent the fluid from leaking. The apparatus includes a rigid housing which encloses in fluid-tight relationship the area of fluid leakage adjacent the sealing mechanism, a vacuum generating device, and means for connecting the vacuum generating device with the enclosed area.