| 摘要 |
<p>A precise flange is formed about a plastic container in a single operation by providing cooperating coining and cooling surfaces (14A,18A) into two mold elements that are surrounded by a cutting die (26). The flange is formed by deforming a thermoplastic container-forming material (25), which has been heated above its glass transition temperature, between the coining and cooling surfaces to coin and form the flange to a predetermined precise shape and thickness. Thereafter the coining and cooling surfaces are moved together while clamping and maintaining the thermoplastic material at the predetermined coining thickness within the cutting die to cut the flange with a precise diameter. Such methods and apparatus are particularly useful for the formation of plastic containers which can be sealed by double seaming.</p> |
