BRAIDING - A NEW PRODUCTION METHOD APPROACH FOR COMPOSITE PRESSURE VESSELS IN AUTOMOTIVE APPLICATIONS

摘要

With the first serial production of a hydrogen fuel cell car announced to enter the market in 2015, there is a prospective mass market for mobile pressure vessel applications. In automotive applications three factors are mainly decisive for a successful integration: low weight, a competitive price range and a safe operation implementation. Composite vessels can fulfill these demands. State-of-the art for the production of the composite structure is wet-filament winding. It is well established for smaller production volumes. However the potential of rise in output is limited. In filament winding only a limited number of usually 1-10 fibres is layed onto a mandrel at once. Braiding in comparison allows the simultaneously deposition of a multitude of fibres, standard machinery allow braiding of more than 200 fibres. A filament wound composite structure lacks fracture resistance under certain load cases. Composite structures known to have better fracture resistance are interlaced fibre architectures, such as braid. This applies especially for impact performance. The braiding process strongly depends on the desired product. The machinery has to be chosen accordingly to application regarding e.g. the number of fibre carriers and their quantities. In automotive applications the dimensions are limited to a certain range due to available build space in the car. This paper will show which parameters have to be considered when setting up a production line for braided pressure vessels. This is done against the background of typical pressure vessel dimensions in automotive applications.