Research on the impact mechanism and parameter optimization of RTP structure layer fusion process

Fiber-reinforced thermoplastic composite pipes (RTP) possess a complex multilayer structure. Apart from the melting process of the reinforced layer, the melting process between the inner and outer layers and the reinforced layer is equally crucial. Factors such as heating time, heating temperature, and pipe diameter significantly influence the degree of tight bonding between these layers. The purpose of this study is to investigate the influence mechanism of the fusion process between the three main layers of RTP and to perform parameter optimization analysis. First, Box-Behnken response surface method and finite element analysis were used to obtain the softened layer thickness under different parameters and to couple the influence mechanism of process parameters on the softened layer thickness. Then, single parameter sensitivity analysis was used to reveal the influence mechanism of each parameter change on the softened layer thickness of the pipe, and then the coupling analysis of the process parameters was carried out. The analysis results show that the softened layer thickness is most sensitive to the change of heating temperature, followed by heating time and pipe diameter. Finally, the optimal parameter combination was obtained through the expected function method, and experiments were conducted on finished pipes.