Crimp rigidity

Gravimetric Method. This method determines the average linear density of the sample, irrespective of the variability of the density of fibers within the sample. It is therefore unsuitable for fiber blends in which the linear densities of the fibers are markedly different. This does sometimes happen, and blends of fibers having different crimp rigidities are sometimes processed to permit changes in yarn properties or fabric properties to be developed later, but generally speaking the staple yarn spinner will try to blend fibers of the same linear density, as this creates fewer problems in production. 

A pretension is applied that varies with the type of fiber and whether the test is conducted wet or dry and is given in a tabulated format without explanation or reference to the crimp rigidity of the different synthetic fiber types. The responsibility for this aspect appears to have been left to interested parties whoever they may be. The tabulated data is reproduced in Table 7. 

There arc basically two standard methods for measuring crimp rigidity. BS 6663. 1986. and ASTM D 4031-95. In the first of these there is Method A and Method B. but Method B is essentially the same as Method A except that the test hank is first relaxed in hot water at 75 C for 10 minutes. Method A is essentially the H.A.T.R.A. crimp rigidity test described by Booth [19] and criticized by G. S. Wray [20]. The instrument is now marketed by SDL of Didsbury, Stockport. Cheshire. U.K. 

Crimp rigidity test. A form of crimp rigidity test used in the UK for the testing of false-twist textured nylon yarns. 

Kratzer scratch (Gerat zum Abkratzen/Schabeisen) scraper kratzfest scratchproof Kratzfestigkeit scratch hardness, scratch resistance mar resistance Krauselbestandigkeit crimp rigidity/stability, crimp resistance Krauselglasfaser crimped glass fiber krausein crimp... 

Krauselung crimp rigidity/ crimp stability/ crimp resistance... 

Crimp tabs Key pad contacts RFC connectors Area array connectors Dimple contacts Microbump arrays Flex-flex Flex internal Flex-flex or rigid boards Flex-rigid boards Flex-rigid parts (flex-flex) Flex-rigid boards and parts Tach panel switches Keyboards Computer peripherals Industrial equipment Inkjet printers Board testers... 

Jeong and Philips [46] studied the effects of fabric structure and mechanical properties on the draping characteristics of fabrics. The fabric cover factor has a large impact on fabric drape because of its effect on the bending rigidity. Yam interactions and crimp are determined by weave stmcture, also influences the fabric drape by modifying the shear rigidity. 

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