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H.B. Fuller - Kömmerling
Adhesives at their best! A comprehensive adhesives portfolio from H.B. Fuller for a reliable production planning enables constant production times as well as safe and optimized processes Words Peter Hirtschulz
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n today’s modern production factories, as we know them all over the world, it is desirable, even necessary, to make the individual processes as plannable as possible. Modern 2-K Polyurethane adhesives can be adapted very well to the individual requirements of the customers or to their wishes. However, there are influences that have a big effect on adhesives, but which cannot be met by one adhesive alone. One major influence that plays a big role in the predictability of processes is temperature. One very important adhesive application in modern RV design is the production of sidewall and roof sandwich panels. In principle there are three different adhesive technologies in use. H.B. Fuller is able to serve
Graphic 1
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all of them. Reactive Hotmelt widely used in the US, Liquid Moisture cure, the main technology in Europe and as a specialty, mainly for bigger Luxury vehicles, is standard 2-K Polyurethane. Reactive Hotmelt is applied at higher temperatures above 100° C, so the ambient room temperature in production isn’t a big issue. Using Liquid Moisture cure products at different temperatures during the production, cannot be balanced and so customers often use different products to overcome the temperature effect. For the usage of 2-K Polyurethane H.B. Fuller has developed innovative products that can easily compensate existing temperature fluctuations on site. The curing behavior of adhesives is linked to the ambient temperature. The pot life is determined at a standardized temperature in order to obtain a certain comparability with other adhesives. Or also to have an indication of the curing time in relation to the prevailing ambient temperatures in production. The reaction of polyurethane adhesives is faster at higher temperatures, which leads to a shorter pot life, and correspondingly slower at lower temperatures, which means a longer pot life (see Graphic 1). Depending on the ambient temperature, the adhesive must be selected accordingly to ensure a certain process time. Since the ambient temperatures are not constant, several pot life variations may be necessary to achieve a safe process in production. To ensure a constant process time, it is necessary to use adhesives with different pot life/curing times. This means storing different pot life variants and deciding which is the most suitable variant for the process depending on the ambient temperature. This is a big challenge in terms of logistics and production
