To assure that polyurethane (PU) resins can be properly processed, pultruders and OEMs have been required to invest in additional hardware and tooling. Many pultruders have also found the need to upgrade existing equipment, or specify new equipment, with higher clamping and pulling capability. In many cases urethane resins require a high percentage of glass fiber, usually roving, to deliver the high flexural modulus that pultruders can expect from the resin. The high fiber content and urethane's adhesive characteristics can require equipment with the capability to process with high pulling and clamping loads. In addition, the fast reactivity of the resin requires that the resin be mixed and injected in a closed system. To accomplish this task a complex injection die and metering and mixing system is required. The injection die gets mounted to the pultrusion die and must allow the reinforcements, veils and resin to come together to be wet-out at what can be high processing speeds.
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