Protecting injection moulding machines against wear When injection moulding fibre-reinforced plastics, the entire flow path, especially the hot runner valves produced with special technologies, is subject to heavy wear. To reduce this stress, a new fire damper valve has been developed, which is made of a material that is particularly wear-resistant and can be machined with high precision. This is necessary to ensure that the valve is durable, while at the same time providing a tight seal even with relatively coarse fillers.