Process Engineering: New Extrusion Process For Seal Profiles

Achieving climate neutrality requires high-quality materials along the entire value chain. In onshore and offshore wind farms, there is a trend towards larger turbines with longer rotor blades and taller towers. The loads occurring here are transferred to the structure. This means that the foundation seals must compensate for large gap movements on a long-term basis, even under extreme storm conditions. In such a challenging environment, the expectations for the service life of sealing solutions are enormous: up to 35 years or more. Depending on the requirements and available installation space, Freudenberg Sealing Technologies offers both large-scale seal profiles and already established seal dimensions made with improved materials for wind turbines. The new LCM system expands the options available in both cases.  

The energy generated on land and at sea is also used for hydrogen production. Alkaline electrolyzers require special materials and seal sizes that are resistant to the potassium hydroxide solution used in the process. Large seal diameters sometimes have to work with extremely delicate profiles with high tolerance requirements. The process industry also requires large seals capable of withstanding aggressive media and high temperatures. Potential applications range from lids and hoods in soldering systems to hot-air ovens in the food industry. The advantages of molten-salt vulcanization can be fully leveraged in producing such specialized seals. This is because the new LCM process offers access to an extensive materials portfolio, enabling highly precise manufacturing of both small and large cross-sections of seals.

Process monitoring: Integrated continuous measurement process and quality assurance

To enable documented monitoring of the sealing profiles during the vulcanization process, Freudenberg Sealing Technologies has implemented a state-of-the-art sensor system. It measures key product characteristics and is integrated into the production process to monitor the vulcanized seal profiles. In addition, an advanced control system adjusts the process based on the still non-vulcanized profile. Now it is possible to produce filigree profiles with a wall thickness of 1 millimeter with a tolerance of 0.1 millimeters. This is an enormous quality improvement from the previous 0.3-millimeter tolerance range. Thanks to this molten-salt extrusion process, the company’s customers now have access to a similarly wide range of materials that was previously only available through molding processes. It also includes sealing solutions approved in accordance with the regulations of the U.S. Food and Drug Administration (FDA). This is how Freudenberg Sealing Technologies is expanding its range of solutions for large-format seals. Customers benefit particularly from the company’s excellent materials know-how and design expertise.