Novel multi roll stack prepreg impregnation machine
Prepreg technology specialist Cygnet Texkimp develops Novel multi roll stack prepreg impregnation machine. The small-footprint machine was developed by the company’s prepreg technology specialists as a lower-cost solution in terms of capital investment, running costs and energy requirements, when compared to conventional prepreg processing. It was designed to manufacture high performance prepreg and towpreg materials more efficiently and sustainably without compromising accuracy of the product, speed, or consistency, and so offer the potential for cost effective prepregs and towpregs to be used more widely. The machine was developed as part of a UK collaboration to develop the technical and supply chain capability to achieve high-grade, composites-intensive components at rate for high-volume markets.
The ASCEND (Aerospace and Automotive Supply Chain Enabled Development) programme is a four-year, £40m project launched in 2021 and led by Tier-1 aerospace supplier GKN Aerospace with funding from the Aerospace Technology Institute (ATI) and Innovate UK. Cygnet Texkimp is a partner in the consortium which is made up of 14 UK organisations including the National Composites Centre.
The Multi Roll Stack is a UD (unidirectional) and fabric prepreg impregnation machine comprising a series of compaction rollers configured vertically. It is a major departure from conventional in-line prepreg machines which incorporate separate compaction stations (compactors) arranged in a horizontal line. In contrast, the Multi Roll Stack features a single compaction module containing multiple impregnation rollers arranged vertically.
The material passes repeatedly around the Multi Roll Stack’s heated impregnation rollers, increasing contact with the rollers throughout the process and reducing the energy required to achieve impregnation of the resin within the fibres. One aim of the design was to reduce or remove the heating-cooling cycle, which is typical in conventional in-line prepreg technologies, so that the temperature of the material remains consistent. This is significant because it results in lower energy consumption and reduced material scrappage, while maintaining consistency and accuracy in the finished prepreg and the performance in the resulting component. The production speed and coat weight accuracy achieved by the Multi Roll Stack mean it is capable of manufacturing precision towpregs with the same resin systems commonly used in the aerospace industry.
By configuring the technology in this way, Cygnet Texkimp has shortened the machine’s footprint by more than 50% (with greater space savings relative to larger machines) and increased processing speeds. Stacking the rollers within one compaction module removes the need for multiple drive motors and heaters, which in turn also reduces energy consumption and cost by more than half compared to conventional prepreg technologies. The machine’s shortened web path also leads to reduced material wastage and the compact design will reduce CapEx costs.
In the last decade, Cygnet Texkimp has designed and supplied more than 30 UD and fabric thermoset prepreg lines to the aerospace, automotive and industrial markets, making it one of the largest suppliers of thermoset prepreg technologies in the world. In 2021, the company launched the Direct Melt Impregnation Thermoplastic Composite Line as the world’s first commercially available thermoplastic composite line capable of using standard polymer, from polypropylene to PEEK, to create high-grade thermoplastic composite prepregs on an industrial scale.