Extrusion International 6-2018

42 Extrusion International 6/2018 MATERIAL HANDLING – CASE STUDY In order to ensure uniform product quality from various manufacturing sites around the world, the company decid- ed to go with ten metering systems made from outstand- ingly durable materials. At its core, the customer’s system depends on the reliable LEWA Ecoflow diaphragm meter- ing pumps – which provide flow rates between 0.5 and 10 l/h – in combination with the company’s proprietary “LEWA Smart Control” technology and a high precision mass-flow meter. Continuous guide signal and measuring instrument feedback ensure sensitive and prompt control with only very minor deviations. Since the metering systems are being used worldwide, minor modifications were necessary for adapt- ing to national regulations. Silane crosslinking is an established process that improves the performance of cables. In comparison to thermoplastic polymers, crosslinked polymers achieve much better results when it comes to resisting heat, deformation and weather effects as well as electric flow and creep behavior. In addi- tion, the process has the advantage of requiring much less energy for the procedure compared to similar methods such as radiation crosslinking. The results are lower operating costs for production and environmental conservation. One company that uses this process is a customer of LEWAGmbH. Depending on the application and product, the customer (a cable manufacturer) uses various types of silane to produce cable insulation, such as aminosilane or vinylsilane. Since si- lanes are usually highly flammable as well as highly reactive in combination with atmospheric oxygen, the systems used for metering must make safe handling possible. For these purposes, the company has been relying on customized me- tering systems from the LEWA pump experts for many years How precisely silane can be metered during continuous plastics processing has a direct influence on the quality of the end product. This is why fast and precise control of the flow rate must always be guaranteed – even when different types of silane are being used for different products. LEWA GmbH from Leonberg, Germany, has a customer that faced this very challenge. The customer is a cable manufacturer that uses various types of silane as crosslinkers and adhesion agents to produce cable insulation. Customized Pump Technology enables Precision Silane Metering in Accordance with national Guidelines Silane crosslinking is an established process that improves the performance of cables. In comparison to thermoplastic polymers, crosslinked polymers achieve much better results when it comes to resisting heat, deformation and weather effects (Source: Fotolia) The LEWA Ecoflow diaphragmmetering pumps are the core of the new systems. Thanks to their modular design, the systems can handle a wide range of fluids, including flammable, toxic, abrasive, viscous, environmentally harmful and sensitive fluids (Source: LEWA GmbH)