REMOVABLE HOLLOW PLUG FOR AIR VENT IN A MOLD

摘要

A removable plug for an air vent in a mold including an annular bushing with a central bore preferably of about 0.8 mm and an annular insert with a central bore preferably of about 0.3 mm snugly fitted into the central bore of the annular bushing is described. The annular bushing is preferably made from an aluminum alloy such as Aluminum 115. The insert is preferably made of a stainless steel alloy such as Stainless Steel 304. The annular bushing is generally between about 5 to 20 mm long and the length of the insert is preferably no more than about 0.5 mm shorter than the length of the annular bushing. In an alternate embodiment of the removable plug of the present invention, a portion of the exterior surface of the annular bushing is roughened to improve the frictional fit between the annular bushing and the hole in the mold into which the bushing is placed. A mold including the removable plug of the present invention is also recited as is a method for making such a mold.