Method for producing plastic envelopes especially for vacuum packed insulation has a plastic strip folded and welded in a continuous process and with cross seals at a set spacing

摘要

A method for producing plastic envelopes with a secure lasting seal, especially for vacuum packed insulation panels has a thermoplastic plastic strip feed (4) folded and edge sealed into a continuous tube by heated press tools (6, 7) followed by cooled press tools. A PTFE film (4) is held into the mouth of the tube to prevent the two sides of the flat tube inadvertently sticking together. The flat tube is collected in a buffer store (14 to 16) from where it is pulled out in set lengths and cross welded and cut to form envelopes for subsequent filling and sealing.