Wide braided fabric

Flat and tubular braids and their tracks. Source Reprinted with permission from Fujita A, Hamada H, Maekawa Z, Uozumi T, Okauji T, Ohno E, Proceedings, TexComp-2, Leuven, Belgium, May 17-19, 1994. Permission from Katholieke Universiteit Leuven. 

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Woven, knitted and braided fabrics for medical textile products are made from yarns that contain fibers, whereas nonwoven fabrics can be made directly from fibers or even polymers. Expanded PTFE fabrics and electrospun webs of micro and nano denier fibers, used in medicine, are examples of products made directly from polymers. All fabrics mentioned vary widely in their construction parameters and, therefore, in the performance characteristics obtained from a given raw material. There is, therefore, a hierarchy of structure. The performance of a final product can be modified from two to four levels of organization. 

Nylons belong to the class of polymers known as engineering polymers that is, they are strong, tough, and heat resistant. We can readily extrude and mold nylons to form a wide variety of useful objects, such as tubing, furniture casters, and automotive air intake ducts. Nylons are commonly spun into filaments or fibers. These can be used directly, or braided, or twisted to form threads, yarns, cords, and ropes, which may be further woven to make fabrics. In their fibrous forms, nylons are used in carpets, backpacks, and hosiery. 

A large variety of hose constructions are produced by the rubber industry for a wide range of applications. To contain transported liquids, usually under pressure, it is necessary to reinforce the hose construction with fabric, yam or short fibres to constrain expansion of the rubber. Although hand-built construction using fabric still represents a proportion of the production, it is also very common to use yams either braided or knitted directly onto the hose liner. For heavy duty purposes it is also necessary to use wire, in a braided form, to either reinforce or protect the hose from external damage. Use of short fibres as reinforcement represents a small proportion of hose production and requires specialised dies for extrusion to orientate the fibres circumferentially. 

CA 68, 3093(1968) (Describes an expl tape approx 5 /8-inch wide fabricated by bonding together with a w-based latex adhesive 8 strands of textile covered detonating cord having a diam of ca 0.06-inch, the expl core of which contd 4 grains of PETN/ft and was enclosed in a textile braid. This tape has sufficient flexibility so that it can be folded back on itself or tied in knots at any point w/o cracking. 

Of the available textile reinforcements (woven, braided, knitted, stitched), many can now be considered to be mature applications. For example, non-crimp fabric (carbon fibre) is used to manufacture the A380 rear pressure bulkhead at 240kg, in mass, 6.2m long, 5.5m wide, and 1.6m deep, this can be classed as a large structure at a smaller length scale, braided carbon fibres are now used regularly for high performance bicycle frames. 

The 21st century has already seen rapid advances in the field of textile-based composites. In addition to traditional two-dimensional woven fabrics, multiaxial non-crimp fabrics are now very widely used, with a rapidly growing number of applications for braided composites. Developments in three-dimensional weaving, combining through-thickness reinforcement with excellent in-plane properties, provide new design solutions for situations where delamination must be avoided. Textile reinforcement is thus providing major new areas of opportunity for composite materials worldwide. 

There are a number of technical functions of cords in clothing. Examples are ties to tighten anorak waists and hoods and shoe laces, which are usually circular or flat braids. In addition to basic mechanical performance, good knottability is needed. Narrow fabrics are used as belts. Webbings are widely used, particularly in a miUtary... 

Although widely being explored, the majority of the automated production of 3D braids is often limited to fabricate constant cross-sectional 3D braid geometry. However, the production of a tubular or bifurcated structure requires variations in the geometry of the cross sections. This leads to manual interference in the production process, which slows the production process and constrains the use of 3D braids to products with small quantities. Thus, development of a fuUy automated process will clear the way towards the production of 3D braids in large quantities and allow the use of 3D braids in wide areas of application. Examples are the preforms in composites, for example, stmctural stiffeners in car bodies or as stents in a medical devices. 

Continuous, aligned fibers are the most efficient reinforcement form and hence are widely used for high-performance applications. However, for ease of fabrication and to achieve specific properties, such as improved strength, continuous fibers are converted into a wide variety of reinforcement forms using textile technology. Key among them at this time are two-dimensional and three-dimensional fabrics and braids. 

Hence, concrete is reinforced with special textile structures such as multiaxial muiti-piy fabrics, braids, and muitiiayer woven fabrics. Glass filaments are widely used owing to their iow price. Carbon fiiaments are also used in special applications but normaiiy are too expensive a fiber material. 

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