JEC COMPOSITES MAGAZINE - Issue #54 - January 2010 - 31

Equipment Epoxy-resin infusion systems for wind-blade manufacturing For specific and high-technology niches, Cannon engineered dedicated mixing heads and dosing equipment that can pour not only polyurethane formulations, but also other types of mixtures (such as epoxy resins) with different physical properties. Fundamental precaution Communication Manager Cannon Afros Division Max Taverna, Communication Director Cannon Group ind energy is one of the most important sectors in the fast-growing market of renewable energies. In this field, epoxy resins are used for the vacuum infusion of windturbine blades. Cannon has recently engineered a new and dedicated range of units to meter and mix significant quantities of epoxy resins that have to be dosed at low output in a fairly long infusion process. The giant blades that catch the wind to propel electric generators are built using a combination of technologies, mainly impregnation of light glass-fibre mats with two-component resins, mostly liquid polyesters and epoxies. These reacting formulations require metering and mixing devices capable of dispensing tons of material into the enormous moulds where the blades are shaped. Infusion machines should combine precision, reliability and easy handling. W Continuous control The new Cannon epoxy-infusion machines are compact, transportable and fully electric dosing units that are equipped with closed-loop output and ratio control systems. This guarantees continuous control over the injection of the liquid resins into the vacuumized moulds, which contain various layers of glass reinforcement. The infusion process can proceed for 2-3 hours or more, and the flow of material varies according to the level of filling requested. A medium-output starting phase is followed by a progressive reduction of flow, due to the resistance and friction created in the mould and to the wetting of the mass of reinforcement. The need to fill the most extreme portion of the long blade moulds with the same proportion of resin over the reinforcement raises the problem of a continuous change of injection rate, thus the need for a closed-loop output control system for both components. Keeping a precise mixing ratio is a fundamental precaution to avoid emissions of non-reacted chemicals at the end of the process. The most common models of Cannon machines for epoxies are capable of dosing from 5 up to 80 kg/min of resins working in a range of mixing ratios, using a long static mixer attached to a dedicated mixing head. The machines can also be fed directly by a standard New Cannon DX 35 models, IBC (intermediate bulk container) or the epoxy resin infusion systems now available from Cannon connected to the central chemicals storage. All available models are equipped with a touch-screen colour panel to monitor and control the machine functions in real time. Cannon has always supplied dedicated solutions that are flexible and highly integrated, including dosing machines and systems for mixing-head movement. Even in the case of epoxy-resin infusion technology, complete turnkey plants can be designed to specific customer applications/production requests. More information: www.afros.it www.cannon.com More information With more than 12,000 metering units installed, the Cannon Group is the world’s leading supplier of dosing systems, mixing equipment and processing technologies for polyurethanes. Cannon designs, manufactures and sells anything from single mixing heads and stand-alone units up to complex and turnkey production plants. Cannon is directly present in 40 countries worldwide through a vast commercial and industrial network. The network involves 1,000 people, working in about 15 production units and local representative offices that supply products, services and technical consultancy to over 15,000 companies. No54 January 2010 / jec composites magazine

http://www.afros.it http://www.cannon.com

JEC COMPOSITES MAGAZINE - Issue #54 - January 2010

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #54 - January 2010