Rotating sealing system for vacuum sealing machines - comprises upper holder for polyurethane sealing disc with vent hole coincident with annular channel on holder

摘要

Improved sealing system for a vacuum sealing machine comprises a rotating sealing head which holds the sealing disc. Discs are mfd. in an elastic wear resistant material, typically a crosslinked polyester-polyurethane. Air is bled from the container via an opening in the sealing disc which coincides with an annular groove on the lower face of the disc holder. A centralising insert at the base of the container has a recess in the base plate with a layer having a surface with high frictional resistance. The layer consists of a solid material, typically a thermoset, e.g. phenolic or epoxy resin with a surface inlay of hard particulate material. USE/ADVANTAGE - The closure system is used in vacuum sealing machines used to screw caps onto containers, has components with improved wear resistance and permits better transfer of torque during cap closure.