Development of a novel polymer bending head system for the production of fuel lines

Abstract

The innovative system for shaping plastic pipes combines the advantages of computerized numerical control (CNC) pipe bending, established for metal pipes, with the thermofixing known for plastics. According to the principle of rapid prototyping, no complex bending tool shapes are required, but each bend is formed separately on the universal bending head. The bending process consists of forming, heating and cooling. In order to achieve the shortest possible cycle times, dielectric heating is used. Tests have shown that a new machine concept is necessary due to the plastic pipes and that conventional horizontal CNC bending cannot be used. It will also be shown that the design and layout of the universal bending head is possible with a suitable polymeric material. For this purpose, the acting forces were estimated and general requirements were formulated for the material. In addition, this material selection was limited by determining the dielectric properties under operational conditions. As a result, a polyetheretherketone (PEEK) type could be selected as a suitable material. The design of the bending head is based on mechanical and thermal simulations with this PEEK.