Interlacement variations in the alternative covering technology D-3F

Abstract

The following study deals with the main interlacement variations and possibilities of the new covering technology D-3F. There are well-known processing technologies for the covering of extruded hoses or other tubular cores in order to increase their radial stiffness, like braiding or spiraling. The main disadvantage of the spiraling layers is the limitation in stability of the single windings, caused by missing interlacements. An advantage might be the fiber deflections and the resulting directed mechanical properties in combination with the achieved productivity. On the other hand, it is impossible to cover cores with changing diameters and resulting local angles higher than the friction angle of the current materials. These forming cores or profiles are often covered by the more suitable braiding technology. Braided structures can be produced stably based on proper interlacement between the two or three thread systems inside. In fact, the braiding technology has its limitations concerning the productivity. The interlacement of the thread, which stabilizes the structure from one side, is the reason for broken filaments as a result of the deflection of the threads from the other side. The number of broken filaments is proportionally increasing with the speed of the braiding process. In order to combine the advantages of both spiraling and braiding into a new productive and fiber-friendly technology, a new machine concept was developed and patented. The new weaving-like binding structure "D-3FG" ("Denninger-3Faden Geflecht") combines the properties of two layers and weaving-like interlacements.