Venting system in a molding tool for a curable or castable material allows gas or steam to flow through but prevents passage of molding material

摘要

The tool has a molding cavity (34) and a passage (44) with an opening into the cavity. A vent (40) in the passage has channels whose size permits gas or steam to flow through but prevents molding material from leaving the cavity. An Independent claim is made for a method for manufacturing a vent insert in which: (a) a disc is cut into two pieces which can be assembled; (b) recesses are machined in each piece to form fingers between each pair of adjacent recesses; and (c) both parts are joined together so that long slits are formed between each finger pair.