Stitching density

In summary, an excessive stitch density causes severe degradation of in-plane strength and stiffness, particularly in bending (Mouritz, 1996) and compression (Farley, 1992). The major reasons for these undesirable effects can be summarized below ... 

Fig. 8.25. Interlaminar shear strength as a function of stitch density for seven layer off-loom stitched glass fiber-epoxy matrix composites. After Adanur ct al. (1995).

Fig. 8.28. Normalized delamination area due to impact as a function of stitch density for a carbon fiber-epoxy matrix composite. After Liu (1990).

Fig. 8.29, Delamination patterns of a carbon fiber-epoxy matrix composite with varying stitch densities.

Karkkainen RL, Tzeng JT. Micromechanical strength modeling and investigation of stitch density effects on 3D orthogonal composites. J Compos Mater 2009 43(25) 3125—42. 

As part of the stitching process, it is very important to have the correct stitch density for the garment this has a direct influence over seam strength, seam appearance and seam extensibility. The factors affecting stitch density are ... 

A normal and consistent stitch density depends upon the product being stitched but can vary from 15 stitches per 2.54 cm for lightweight knitwear fabrics to 9 per 2.54 cm for heavier weight materials. 

Stitch density refers to the tightness of the stitches in a knitted structure. It is calculated by multiplying the frequency of the columns of stitches... 

Scanning electron microscopy Stitch density, woven fabric count or braid geometry Fabric thickness Mass per unit area Relative density Porosity Fiber type... 

The strength of the seam should be equal to that of the material it joins in order to have a balanced construction that will withstand the forces encountered during use (Nayak et al., 2010). The transverse strength of a seam is determined by a number of factors, such as stitch type, stitch density, thread strength, thread tension, needle size, and needle type. It will be observed that the seam failure in a garment can occur because of ... 

An increase in the values of these factors increases the fabric resistance to seam slippage. Seam slippage depends on weave, fabric raw material, type of seam, stitch density, and sewing thread tension. 

Table 9.6 Interrelationship between stitch density and nonwoven strength (web 60% PP primary fibres/ 40% PP reclaimed fibres) as related to mass per unit area ...

The key feature of circular weft knitting is to produce fabric structures in a tubular form. Figure 6.5 shows a tubular weft-knitted fabric developed for vascular stent application on a circular weft knitting machine with a small-diameter cylinder. The diameter and stitch density of a tube can be adjusted by varying the cylinder diameter and machine gauge, respectively. 

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