VACUUM BAG FOR HOT DRAPE FORMING

摘要

A method and an apparatus for conforming a blank onto forming surface sections of a forming tool by drawing a vacuum against an elastic vacuum bag for transmitting forming forces from the elastic vacuum bag to the blank. The elastic vacuum bag includes at least one bag section having a different stiffness than other bag sections. The at least one bag section is an elongated bag section having a stiffness larger than that of surrounding bag sections. The location of the elongated bag section of the elastic vacuum bag corresponds, when the elastic vacuum bag after completion lies against the forming surface sections having the blank in between, with an elongated forming surface section of the forming tool where the blank requires a forming force being larger than that of the surrounding bag sections.