Method for monitoring the melt status when producing a plastic weld seam

摘要

The method involves determining and storing electrical state variable e.g. permittivity, of plastic parts (7, 7') e.g. plastic sheet or plastic film, of a thermoplastic material in a region of weld seam during temperature charging of the material for forming a plastic melt material for the production of the weld seam. A change of the electrical state variable is determined by offsetting the stored values of the state variable with each other and/or with additional measuring-or record values. Results of the change of the state variable with target value or benchmark values are compared.