Study on the simulation of annular axis braiding process and braiding angles’ prediction method

A common braiding machine cannot perform continuous braiding using closed annular axis mandrels. To solve this problem, a modified vertical braiding machine was made to braid composite preforms with irregular cross-section mandrels. The finite element method was used to simulate the braiding process, and an efficient method was also derived to predict the braiding angles. The results show that the predicted braiding angles are basically consistent with the actual braiding angles, and the braiding angles at distinctive locations on the braided preform recorded differences of up to 10° or more than 30%. Braiding process simulation via the finite element method can thus effectively and vividly reflect the yarn path on the preform. As such, the braiding angles on the braided preforms can be realized through projection and surface flattening with much better accuracy. It also resolves the difficult problem often faced in measuring the braiding angles at the corner of the mandrel and provides a solid basis for continued research on the performance of its composite reinforcement.