The folded film is a kind of heat shrinkable film, is a film folded and then rolling, work in with L bar shrink machine. As everyone knows when a product requires shrink, we must first consider shrink film'size, and select shrink film width, and then determine the shrink machine model, if sleeve machine can in residual film length product ends set aside adequate only, how much can allowance according to the product height and cuffs size setting, this calculation method is relatively simple. And the folded film need to consider compressed size, and with the sealing and cutting machine of different margin requirements, in order to facilitate the understanding, Qingdao Ausense illustrated the way in order to describe the calculation method of folded film: