Double layer weaves

Fibre and weave Air permeability (m h at 20 mm w.g.) Weight (g m-2) Thickness (pm) Typical filter suitability 

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Conventional standard weaving machines can create this type of shell three-dimensional woven fabric, if two layers are woven with areas of hollow and other areas of non-hoUow fabric. To avoid the potential danger of recoding fabric parts, a double-layer fabric should completed at the non-hollow zones with a long floating single-layer weave or with another double-layer weave having joints of warp ends or weft threads between the two layers. 

Figure 2.11 Cross-section through a double layer weave, showing the finer weave at the upstream (filtering) surface and the coarser at the downstream surface (Madison Filter).

Table 2.10 Examples of double layer weave cloth qualities for liquid filtration (Sefar). ...

Another type of shell three-dimensional woven textile was suggested in 1929. A combination of Jacquard shed formation and shuttle weft insertion creates a flat woven fabric with areas of double and single layers (Lippert, 1929). Depending on the coti-tour of the double-layer area, this part of fabric can be cut and unfolded after weaving, for example, to become a hat geometry (Figure 4.4). 

Double-layer fabric weave for hollow zones... 

Figure 4.7 Weave design for double-layer fabrics with hollow and joint zones (hatched square on right side removed lifting point).

If a double-layer hollow area of the fabric is surrounded by a joint weave, the borderline between the two could be regarded as a woven seam. Unfolding of this hollow area can be done, for example, by inflating, and this may require a certain level of seam strength. The details of weave design have a significant influence on the strength of woven seams. 

Figure 4.9 Double-layer fabric design with partial hollow and joint zones. Left weaving machine, right design of hollow and joint double-layer fabric zones.

The presence of layers of mineralized fabric suggests that the silk fabric may have been wrapped around the blade, but the fabric was altered in the diagenetic context. All evidence of fabric was destroyed on the reverse side of the spearpoint. Furthermore, the shift in the geometric relation of the layers with the same attributes, as indicated in the mapped area, tends to support the wrapping of one fabric rather than the possibility of double cloth or some other compound fabric variant. The Han warp-faced compound tabby (unbalanced plain weave) has two sets of warp that are integrated into one layer and may be considered a compound fabric with complementary warp (16, 17), The reason for the placement of fabric and weapon in the burial context remains a crucial question for reconstruction of past decision making. 

A cruciform structure is shown in Figure 9.18. The 100% fill fiber of each flap goes through the intersection. Each flap consists of four layers, and again they are connected by layer-to-layer interlock weave based on a plain weave. The typical construction of each layer is 16 x 16 ends and picks per inch in the case of 6K carbon fibers and 16x8 ends and picks per inch in the case of 6K carbon warp fibers and 12K carbon fill fibers. A double cruciform with all sides tapered was also woven using a modified narrow fabric shuttle loom. 

To integrate the ultrasonic sensor to textile structures as well as to form electric circuits in the stmcmres, silver-plated nylon yarn with a linear resistance of <50 n/m and with a yam count of 312/34f x 4 dtex is used. To prevent formation of short circuits in the textile-based electric circuit, conductive yams are hidden in the stmcture. A fabric stmcmre is considered as a double-woven fabric, and conductive yarns are placed in the middle layer of the stmcmre. The set of warp yams of the upper layer are linked to the set of weft yarns from the bottom layer, and thus the two layers are held together. A four-harness satin weave is chosen for both layers. Fig. 3.2 shows the diagram representing the drawdown, threading, and lift plan of the double-woven cloth together with the 3D-graphical representation of the woven fabric stmcture. 

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