摘要 |
An improved method for producing impregnated reinforcing threads is disclosed. The method involves impregnating glass, carbon or aramid fibers with a twist <=120 turns/m with a polymer dip, drawing the impregnated threads through a nozzle, drying the threads superficially in a first heating zone where they are kept moist in the core, and then providing them with a twist up to 400 turns/m in a second heating zone in which they are heated to fix this twist. The fibers are intimately impregnated with polymer, so that the impregnated threads have high fatigue strength, and a compact, constant cross section throughout their length. The impregnated threads are particularly suitable for reinforcing driving belts and high pressure hoses; they can be made into wovens and scrims which, in turn, can be used for reinforcing tires, conveyor belts and the like.
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