Research And Optimization On Braiding-Winding-Pultrusion Process Of Composite Pipes

In daily life and industry composite pipe fittings for its design can be widely used in aerospace, defense, transportation and others fields. However composite pipe in some specific areas are not being used The composite pipe which is good performance is a new product of urgent need in the composite material industry. There is a new process called braiding-winding-pultrusion process to produce the composite products. The principle of the braiding-winding-pultrusion pipe is that the braiding and winding fabric on the core shaft is driven through the pultrusion under the action of external force, and that the fabric impregnated by resin is of the solidification under the function of the mould heating and Die extrusion, and that in the end the pipe is got by cutting.Braiding-winding-pultrusion is not the simple sum of individual process. The mechanical property of the braiding layer and winding layer is different. The formation of two layers are under the interaction and influence. The pipe which is braided and winded is under the action of simultaneously extrusion and stretch during the pultrusion. Which leads to change the pattern of yarn and gel content. The influence of the new process parameters on the pipe curing is uncertain. It takes a long time to do simple experiment whose scientificity is insufficient. The product quality is not guaranteed. This paper do the following research on braiding-winding-pultrusion process:firstly, we get the yarn position distribution changes relation of the each layers of pipe. So the new lines design requirement which assure uniform strength on the yarn can be founded. According to the position distribution of the braiding and the winding yarn and the design requirement of pipe properties, this paper designed the braiding lines and winding lines individually. Secondly, under this new kind of the linear design, according to the principle of composite curing, the composite pipe heat transfer model and the curing dynamical model were modeled. We took use of ANSYS developed the curing process numerical simulation procedure. Trough the simulation of three-dimensional resin thin-walled pipe and the experimental verification to analyze that the process parameters affect the curing temperature and curing of the process of forming the new pipe.The influence law of initial temperature of pipes, heating process and pultrusion speed on solidification process of the new process for pipes is attained by the simulation analysis for the fitting. The pattern design of pipe yarn is verified reasonable through the test of yarn angle for pipes. The nondestructive testing is operated on pipes, the result shows that the fitting has no obvious damage under the guidance of the line type theory. The on-line temperature testing is operated on pipes, the result shows that the simulation is identical with the actual production process, which can guide the actual production.