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A phenomenological inquiry of the islands of Lewis and Harris provides a foundation for the cloth that is made there, which in tag and reputation conveys its relationship to “place.” Tweed is a cloth historically born out of place-based tensions, which express themselves socially and materially in the vehicle of this woven proxy. Using Harris Tweed as a primary case study, this tension is addressed in a narrative examination of insiders and outsiders to conclude that the fabric of tweed—as well as the nationalisms, social fabric, and industry so iconic to it—is constructedwithcontrasts and differences, and not in spite of them. This examination proves relevant to tweed’s historic role as “British National Costume,” especially in light of the 2014 Scottish independence referendum and the 2016 Brexit vote. [ABSTRACT FROM AUTHOR]

The measurement and control of yarn tension is important in textile technology. This paper presents a two channel architecture surface acoustic wave yarn tension sensor, which is able to provide a sensitivity about two times bigger than the previous one. The design and the fabrication of the devices are also presented. A mathematical analysis shows that the output frequency of the sensor varies linearly with the yarn tension. To test the performance of the sensor, an experiment is carried out to obtain the output frequencies in different yarn tension. The results show that the sensor has a sensitivity of 8234 Hz/N (80.75 Hz/gf), and the sensor is capable of measuring a range of 0–0.196 N (20 gf) yarn tension with a relative error of 2% and a hysteresis error of 3%. [ABSTRACT FROM AUTHOR]

Precise pile height is an essential quality measurement for sculptured-style jacquard carpet. Constructing correct the yarn tension model is the key to accurately control carpet pile height during manufacturing carpet. This paper described a standard tufting equipment system with essential components in the yarn path. First, the relationship of pile height and pile tension is formulated. Then, the A. P. Minakov Euler formula is introduced into yarn tension modeling which including the yarn guides, sub-line frame, and puller rollers parts. Finally, this tension model is validated by comparing yarn tension simulation result data and experimental measuring data. [ABSTRACT FROM AUTHOR]

Tension control under processing in textile engineering has been discussed in the paper. The material forms from spinning to downstream processes have been analyzed. Special features of tension control under typical processes have been introduced; different properties and the tasks of the tension control have been studied. Based on the above work, the paper has put forward the developing route of tension control technology in textile engineering, which could help bring up intelligent machinery for the need of production of remarkable textiles in market. [ABSTRACT FROM AUTHOR]

Continuous hard protective layers on soft substrates working under elastic deformation conditions are prone to uncontrolled cracking and detaching from the substrate during bending and straining. Implementation of a noncontinuous hard pattern deposited on the surface allows such an antiwear layer to freely deform with the substrate. The idea was demonstrated for patterns made of regularly spaced, micrometer range sized nanocomposite islands. The nanocomposite used consisted of an epoxy resin matrix and superhard silicon carbide nanoparticles as a reinforcing component. Good dispersion of nanoparticles in the matrix was verified by means of atomic force microscopy. The significant improvement in wear resistance was measured under an applied load in the millinewton range using a custom-made microtribometer, and in the newton range using ball-on-disk apparatus. Such a system can be applied in textile machines and elastic yarn tensioners for damping the longitudinal component of vibrations, largely influencing the quality of the fabric obtained. [ABSTRACT FROM AUTHOR]

A new creditable and effective multiaxial circular tensile tester (MACTT) with 16 load sensors installed around a circumference has been developed. The new tester could be used to measure tensile properties in various directions with one sample simultaneously under the same initial conditions. As a result, not only an error could be reduced, but also the experiment samples and time could be saved. The experimental results showed good agreement with the theoretical approximate values calculated based on Hooke's Law. We also compared the stress distributions obtained by the new tester with those tested by the Kawabata's Evaluation System (KES) instrument and the results confirmed that the new tester was theoretically reasonable and practically feasible for measuring orthotropic tensile properties of the fabrics with symmetrical structures, and that the new tester could also be used to test and evaluate the anisotropic tensile properties of fabrics with no orthogonal main axes. [ABSTRACT FROM AUTHOR]

It is shown that tension applied to fabric which is then permanently set by steaming under pressure for a short time has a significant effect on fabric dimensional properties. Increasing levels of stretch applied to fabric before pressure steaming resulted in decreases in fabric hygral expansion and relaxation shrinkage and also lowered fabric shrinkage that resulted from permanent setting. The setting conditions resembled those used in conventional pressure decatising, and it is suggested that in batch decatising, precise control of the length and width of fabric as it is batched up with the wrapper before steaming under pressure could enable predictable changes in fabric dimensions, relaxation shrinkage and hygral expansion to be obtained. [ABSTRACT FROM AUTHOR]

A previous study showed that the torque in worsted wool yarns could be measured directly when the yarns were in the form of a hank under tension and that the torque could be split into two components, (a) the torque due to the applied tension and (b) the intrinsic torque at zero tension. This approach was applied to analyze the torque due to tension for a wide range of ring-spun worsted wool yarns of different structural parameters including yarn count, yarn twist and fiber diameter. The torque due to tension was measured on unsteamed and steamed yarns in dry and wet conditions and the data analyzed by applying mechanical models of yarn torque to estimate the yarn packing fraction. By using an effective linear density to evaluate the torque data, an estimate of the packing fraction of 0.63 allowed prediction of the torque in worsted wool yarns prepared from 18 to 24 micrometer diameter fibers across a wide range of yarn counts (16-80 tex) and wet and dry test conditions, and this approach was tested on some representative commercial wool worsted yarns. The effect of setting of worsted wool yarns on the torque due to applied load and the packing fraction was also identified and setting was shown to have little effect on the yarn torque due to tension. [ABSTRACT FROM AUTHOR]

The relationship between the ratio of the applied force on warp yarn by backrest roller to the warp tension, and the radius of backrest roller, the vertical position of backrest roller and the horizontal position of backrest roller with variations in warp beam radius during weaving process has been studied. The optimum values of the parameters have been calculated using a computer programme with the aim to minimize the variation in warp yarn tension during weaving process from full to empty warp beam. The results show that the increase in vertical distance between backrest roller and warp beam radius of backrest roller and horizontal distance between backrest and warp beam towards inner side causes lower variation in the ratio of force applied on warp sheet by backrest roller and warp tension during weaving process. [ABSTRACT FROM AUTHOR]

The complex behavior of nonwoven structures can be studied by tensile tests. To understand the influence of mesoscopic phenomena on macroscopic behavior, the whole thermomechanical behavior was considered. During uniaxial tensile tests three parameters were measured: the load, the strain, and the temperature on the surface of the specimen. Mesoscopic phenomena corresponding to a rise of temperature are said to be dissipative. Two nonwoven structures were considered: a needlepunched and a thermo-bonded fabric. The needlepunched structure was quite anisotropic in terms of the strain field as well as the temperature. The dissipative phenomena involved were the anelastic extension of filaments and their failure. The thermo-bonded structure was more isotropic but was also a locked structure. The mechanical behavior was similar in the two directions and a rise of temperature was noticed during the whole test as a consequence of the failure of the bonded points, the anelastic extension, and the failure of filaments. [ABSTRACT FROM AUTHOR]

When a loom is stopped and restarted, there is often a start-up mark (stop mark) on the fabric where the local pick density deviates from the normal value. The presence and severity of the start-up marks have a direct impact on the value of the fabrics produced. The cause of start-up marks in woven fabric includes cloth fell drifting due to the relaxation of the warp and the fabric, and the loom's dynamic characteristics when starting up. Several methods have been used to reduce the effect of start-up marks. In this study a new method to eliminate the start-up marks has been proposed. In this approach, the warp tension is lowered to near zero when the loom stops, and the loom parameter is readjusted when the loom restarts. A main advantage of the current approach is that its effectiveness is essentially not affected by the time duration of the loom stoppage. The low-tension method for startup mark prevention can be implemented on any looms with digital let-off and take-up controls. The procedures to control the cloth fell position to prevent start-up marks are described. The method has been tested in commercial operations producing different styles of fabrics, demonstrating its simplicity, flexibility, as well as effectiveness. [ABSTRACT FROM AUTHOR]

We evaluate the known solutions regarding the tensioning of yarn in the operations of winding, warping, doubling, etc. The conventional tensioners that have so far been used in the textile industry are described and analysed. We present our own original design for a frictional electromagnetic tensioner in which the nipping load, applied to several ferromagnetic, flexibly inter-coupled nip plates (barriers) is induced by the poles of an electromagnet. Under each barrier (nip plate), the thread or yarn is imparted with part of the tension gain. Tests in which the practical operating performance of the electromagnetic tensioner was compared with that of the conventional disk and compensating tensioners showed that the electromagnetic tensioner was significantly superior. [ABSTRACT FROM AUTHOR]

Different kinds of rotor-spun composite yarns are produced by combining staple fibers with filament yarns under various filament overfeed ratios on a modified open-end rotor spinning frame. The effects of filament over-feed ratio on the surface structure of composite yarns were studied and the results showed that the filament overfeed ratio had a remarkable effect on the pathway of the filament in the composite yarns. As the filament tension increased with decreasing filament over-feed ratio, the filament moved from the surface into the center of the composite yarn, the pitch of the filament pathway increased and the filament twist decreased gradually. The surface structure of the rotor-spun composite yarn was improved in comparison with the normal rotor-spun yarn. [ABSTRACT FROM AUTHOR]

Methods were developed for calculating the temperature distribution, draw ratio, and tension forces in vertical spinning of polyester and polycaproamide fibres based on anonstationarysystem of description. It was shown that in comparison to a steady-state system of description of the take-up tension force differed by one order of magnitude, while the tensile forces were commensurate. The basic channels of controlling and stabilizing the quantitative and qualitative indexes of the spun fibre are noted. [ABSTRACT FROM AUTHOR]

Air drag on yarn and package surfaces affects yarn tension, which in turn affects energy consumption and ends-down in ring spinning. This study investigated the effects of yarn hairiness on air drag in ring spinning. Theoretical models of skin friction coefficient on the surface of rotating yarn packages were developed. The predicted results were verified with experimental data obtained from cotton and wool yarns. The results show that hairiness increases the air drag by about one-quarter and one-third for the rotating cotton and wool yarn packages, respectively. In addition, yarn hairiness increases the air drag by about one-tenth on a ballooning cotton yarn. [ABSTRACT FROM AUTHOR]

Presents a study which focused on a theoretical analysis of tension and pressure decay of a tubular elastic fabric. Theoretical analysis; Methods; Measurement of tension decay of elastic fabric.

The frame of a string instrument is subject to a large tension force when the strings are installed. Intuitively, one might expect that the frame would be stiffened by the strings. Experimental data and a theoretical analysis are presented to show that this is not generally the case. An archer's bow is much stiffer when it is strung, but a tennis racquet is softened when the strings are added. As a result, the mode frequencies for transverse vibrations increase for a bow and decrease for a racquet when the strings are added. The effect of the strings depends on the extent to which the frame is bent at equilibrium. [ABSTRACT FROM AUTHOR]

The section of "Air-Jet Weft Insertion" presents information on the influence of force on the weft yarn and yarn characteristics. The section includes analysis of various researchers on the tension profile of the weft yarn during weft insertion. It informs about factors that influence the peak tension during weft insertion and states that the maximum tension is lower when the winding tension on the prewinder is reduced. The section also informs about those researchers who stressed on the importance of the tension with which the yarn is unwound from the package and wound onto the drum of the weft accumulator.

The section of "Air-Jet Weft Insertion" presents a general review of weft-insertion elements. Researchers found that the velocity of the yarn depends to a large extent on its tension and especially on the method of feeding the yarn to the nozzle. They found that quality of yarn could be enhanced by positioning weft accumulators between the weft bobbin and the insertion device, which permit the unwinding of the yarn package at a constant speed and minimize tension variations during its unwinding. The section informed how lowering of insertion time by reducing balloon forces improves performance of textile machineries.

In the preceding paper, an energy method for performing calculations in fabric mechanics, together with appropriate computational techniques, was described. The present paper contains examples of applications of this method to woven fabrics, particularly to various models of plainweave fabric subject to tension, but also briefly to fabric-bending and to other weaves. [ABSTRACT FROM AUTHOR]

The article investigates the occurrence of yarn tension during rotor-spinning. In open-end spinning, several forces act upon the yarn within the rotor such as frictional forces, centrifugal forces, Coriolis forces, gravity and air-drag. The maximum yarn tension occurs in the rotor's withdrawal tube. Tension at the rotor wall is relatively small. Yarn tension is affected by yarn count and rotor speed. There was a difference between the calculated and measured yarn tensions due to the following possible factors: the yarn was subjected to air-drag inside the yarn tube; the occurrence of frictional force; and the length of the yarn between the exit of the yarn tube and the tension-measuring device was subjected to air-drag.

The article cites a comparative study on the frictional behavior of ring-, rotor- and friction-spun yarn in the same fiber. It recognizes the significance of friction in the surface property of yarn since yarn encounter friction in various ways during the processing and in actual use of yarns. As stated in the article, tension that leads to frequent yarn breaks during the process can be enhanced through a high friction. And thus, both the processing and actual use of yarns are affected by the frictional characteristics of yarns. A table depicting the specification of fibers is provided. The result of the study found that friction decreases as the number of warps, the input-tension level and fiber fineness decreases and the speed and twist level increases.

The friction-spinning process involves a number of parameters, some of which may be the key factors to which attention is directed during the design of a commercial spinning frame or in carrying out adjustments required to make it operate successfully. It is of primary importance to explore the essential relationships between all these main physical factors and particularly to have an exact knowledge of factors affecting the yam tension during yam formation. For this reason, a study of this problem based upon the principle of conservation of energy in a system is made and an approximate equation derived to relate all the parameters involved. [ABSTRACT FROM AUTHOR]

All investigation is reported of factors (i.e., frictional behaviour and tensile properties) relating to the breakage of nylon 6.6 tow, consisting of many thousands of fine monofilaments, during a commercial process in which low is drawn by passing it over a series of rotating steel rolls. In a simulated-test experiment, the frictional behaviour was determined of a stationary length of the fine-filament tow lapping a rotating steel roll with different surface finishes. The friction depended on the roll speed, the effective load, the viscosity of the aqueous ‘finishing’ solution, and the roll-surface finish. Filaments began to break when the effective coefficient of friction reached 0.40–0.45. Friction (and filament breakage) were least with dry tow and were largely independent of roll-surface finish and relative sliding speed (above about 2 ft/min). The addition of the aqueous ‘finishing’ solution used commercially reduced both the yield and the ultimate tensile strength of the nylon (water being the effective weakening agent) and increased the friction of the tow against the roll surface. Friction increased with increase in solution viscosity and this, together with a marked speed effect, indicated hydrodynamic-type lubrication. This was promoted, with a higher relative sliding speed being attained before filament breakage, by the use of a medium-to-rough roll-surface finish. Friction due to viscous sheaf can be reduced by decreasing the product of the relative sliding speed and the fluid viscosity. The factors that may be applied to the commercial process to reduce filament breakage in the drawing of fine-filament tow are outlined. [ABSTRACT FROM AUTHOR]

The differe nces between the ring spinning and compact spinning are compared and analyzed. R ing spinning fra me differe nces between the ring spinning and compact spinning are introd uced . The yarns , made by the same material and technique parameter , are using different spinning methods. Based on analyzing the quality of the yarn , including calculation of mass variations ( CV"' ) , tension , periodic mass variations , hairiness etc , we know that the tension of yarn made by compact spinning is better than the ring spinning and the cvm and periodic mass variations are smaller. Meanwhile , some disadvantages of compact spinning are mentioned according to produce line. [ABSTRACT FROM AUTHOR]

Electronic band structures of single-walled silicon carbide nanotubes are studied under uniaxial strain using first principles calculations. The band structure can be tuned by mechanical strain in a wide energy range. The band gap decreases with uniaxial tensile strain, but initially increases with uniaxial compressive strain and then decreases with further increases in compressive strain. These results may provide a way to tune the electronic structures of silicon carbide nanotubes, which may have promising applications in building nanodevices. [ABSTRACT FROM AUTHOR]

An exact and applicable mathematical model is the basis of computer simulated Multibar lace fabric. In this study, a spline curve is used to simulate the loop structure of Multibarlace fabric. The number and position of control points are determined for stitch, inlay and fallplate lapping. Thus, theoretical models are built for each type of lapping, and deformation of stitch brought about by yarn tension is also taken into account. Moreover, the displacement theory and calculation formula are given. VC++.net is used to develop the simulation program. The real Multibar lace effect of the simulation proved that the model is rational and applicable. [ABSTRACT FROM AUTHOR]

Statistical modeling showed that there can be important scattering in the spectral characteristics of the tension compensators (TC) used as warp thread tension stabilizers in winding on the warp roller due to statistical scattering of the values of the parameters. The statistical model of TC showed that statistical scattering is not only reflected in the type of the average frequency characteristic of the tensioner accumulator but is also a function of the ratio of the tensioner coefficients, in particular, the ratio between the natural frequency of its vibrations and the damping factor. If the scattering is LOW at a higher damping level, at a low level, the scattering of the frequency characteristics is relatively HIGH and can affect the nonuniformity of the thread tension, and this must be taken into consideration in synthesizing an automatic central system for controlling thread tension. [ABSTRACT FROM AUTHOR]

The section of "The Production of Woven Fabrics" focuses on papers dealing with technicalities related to textile weaving. A research paper from Russia presents details of a device for measuring fell displacement during weaving. Another paper discusses influence of factors like the number and positions of the heald shafts, the type of weave, coefficient of friction between warp, fabric and the diameter of the winding on the warp beam. The excess tension theory has been formulated by a researcher suggests that the beat-up force is equal to the difference between the warp tension and the fabric tension.

A preview of the product range for tension meters from Hans Schmidt & Co. GmbH is presented, which will be exhibited at the International Textile Market Association (ITMA)-China International Textile Machine Exhibition (CITME) 2012.