In our engineering projects, we support our customers in the development of highly utilized fiber composite components as well as in the development of the corresponding manufacturing processes including the associated process parameters. Winding processes play a significant role in these engineering services. In order to successfully and economically exploit the potential of this well established process for the manufacture of fiber composite components with complex laminate architectures, adjustments to the standard process are required. For example, the manufacturing effort increases significantly for fiber angles below 40° to the winding axis, since slippage of the rovings in the turning area must be prevented. The conventional method of wrapping the ends of the winding core leads to a significant increase in material consumption. Below a deposit angle of 30°, however, the holding forces applied in this way are then generally no longer sufficient and the use of mechanical aids is necessary. Conventional winding aids consist of endless strips from which pins stick out at a defined spacing (Fig. 1). Neither the pin spacing nor the pin length of these standard solutions are bespoke to the component to be produced. In addition, these aids are difficult to handle and can damage the rovings.
Our aim was to develop an inexpensive and easy-to-manufacture fiber routing device that simplifies the winding process. The above-mentioned disadvantages of the state of the art were to be overcome so that even complex laminates could be wound easily, reliably and trouble-free. Based on our experience with the winding process, an alternative to the commercially available winding pin strips (Fig. 1) was developed: The individualized winding pin rings (Fig.2). We applied for a pa-tent for our development under the title „Deflection device for fibers on a winding core and use of the deflection device“. This has now been granted by the German Patent and Trade Mark Office in April 2021.
For our newly patented winding pins, we use custom CAD adjustments and 3D printing to increase the efficiency of traditional winding processes. CAD-assisted geometry design and additive manufacturing make them quickly available and, when viewed as a whole, cost-effective. LZS winding pins are also reliable, robust and fast to attach on the winding core thanks to the 1-click-system. Thus, they enable an increased productivity of the fiber winding process while saving material at the same time. The individual adaptation to the customer-specific geometry and the variable arrangement of the pins also guarantee a reproducible gain in component quality and thus better mechanical properties (Fig. 3).
More information: www.windingpins.com
Figure 1: Conventional winding pin strip consisting of aluminum strip and hardened steel nails
Figure 2: Additively manufactured winding pin rings with different geometries
Figure 3: Optimal placement of fiber rovings through individual coordination of component design, winding pin geometry and manufacturing process