Process and apparatus to evenly form an air flow valve

摘要

A process for manufacturing an air flow assembly having a valve disc within a bore. A first support is inserted into the bore from below the valve disc, and a second "floating" support is inserted from above the disc. The second support "floats" relative to the disc upon a fluid receiving member such as an inflatable bellows. As the fluid receiving member allows the second support to float when contacting the disc, any inconstancies of the disc are compensated by the "floating" second support. As the disc is squeezed between the supports heat conducted from heaters causes the material of the disc to be extruded radially outwardly into contact with the bore to obtain a consistent thickness at the disc outer periphery.