Mathematical model for warp tension with various back rest settings and relationship with technological parameters

In the textile industry, in order to better control loom warp tension and obtain better quality fabrics, it was very pivotal to analyze the influence of mechanical and technological parameters on warp sheet during weaving. When warp ends are continuously subjected to tension variation numerous number of warp breakages may occur and as a result the quality of fabric produced as well as the loom production efficiency is impaired. In the fabric manufacturing process, warp breakages cost in weaving are far higher than in all other stages of production. Uniform fabric density and cover factor in warp & weft way is vital for high quality fabrics such as technical textiles and smart textiles. So author attempt to model the tension in variation along the warp sheet from the weaver’s beam up to the fabric formation zone under set of assumptions in this paper and derived a linear model which can be used to study the behavior of fabric fell. In this study, the effect of the backrest roller type and position on the physical and mechanical properties of fabrics was investigated. Author has measured warp tension with computerized electronic tension device and shown with mathematical module and experimental data, the influence of backrest parameters on weavability

Experimental analysis of ground water for its recycling in water Jet Weaving

The rapid increase in synthetic fabric production promotes the development of water jet looms and water jet weaving technology. Water jet looms are particularly characterized by their high insertion speeds and low energy consumption. However, the main drawbacks of these machines are their excessive water consumption that leads to water wastage. Even though water is a finite, valuable resource and should be used in an effective manner, very little research has been focused on the recirculation of used water and the usage of ground water in water jet weaving. Therefore, the author attempts to design a filtering system that can recirculate the water used in water jet weaving. The water quality of ground water has also been analyzed for its suitability in the weaving process. In order to have a uniform weft that minimizes greigefabric defects and mitigates machine damages, an experimental analysis was executed. The acquired data shows the parameters of ground water that should be controlled during recirculation. Finally, an objective assessment of test results was used to develop a suitable, simple, and cost effective filtering system. The system can be utilized to recycle ground water and to minimize both water wastage and consumption in water jet weaving

Designing of tension control Device to minimize tension variation across Weaver’s beam

The tension variations across the width of the weaver’s beam cause uneven tension in the fabric formation zone. As a result of the tension variation, the woven fabric tends to have fabric defects, such as non-uniform fabric density and differential dye take–up at various places on the fabric. As the warp ends are continuously subjected to varying tensions, warp breakage frequently occurs. As a result, the quality of the fabric produced suffers and there is reduced loom efficiency. However, uniformity in the fabric density is crucial, especially for technical and smart textiles. In this paper, the authors have attempted to model the varyingtensions across different segments of a warp sheet under a set of assumptions and derived a linear model. Furthermore, a prototype of an automatic tension control device is instrumentedwith two different positions which are located one meter apart and allows the tension variations across the warp-sheet to be practically observed. The measured average tension shows that variations in the internal tension on different segments of the warp-sheet can be minimized or even completely eliminated over time. With the implementation of a related experiment, the authors have shown the effectiveness of this automatic tension controller and its strong implications for the industry

Development Of mathematical model to select best technological parameters In sizing

The sizing process does not add value to the grey fabric, but it is critical to the improvement of weaving efficiency especially for cotton and cotton blend fabrics. With the advent of technology, weaving speeds have been greatly ameliorated and the significance of correct size applications has been thoroughly explored. Since the correct size application is primarily characterized by the size percentage, the technological parameters for proper sizing were chosen through experimental trials and acquired prior knowledge. Thus, a scientific approach to determining the technological parameters is essential to the textile industry. To fulfill the aforementioned need, the authors have developed a mathematical relationship that relates technological parameters involved in size applications. The practical utility of the derived equations were also highlighted. Experimental trials, carried out with poly/cotton yarn on a single yarn sizing machine, confirm the validity of the model developed. Furthermore, empirical findings published in internationally renowned reference books on sizing were also in accordance with the analytical results established. The mathematical relationships developed can be exploited to calculate the optimum parameters of the sizing machine and to obtain the required quality of sized yarn.This approach does not require carrying out costly trials and therefore has positive industrial impacts. Keywords—Mathematical model

Automatic in-line moisture control system for weft package on a weaving machine

The competitive woven fabric production moves from shuttle weaving to shuttleless weaving in order to acquire higher production rates in tact with good quality. The efficiency of the loom production not only depends on the loom speed but also on the rate of loom stoppages during the weaving process. The loom stoppages can be occurred due to various reasons and the frequency of such occurrence will determine the rate of loom stoppages. In addition to the reduction in efficiency, loom stoppages seriously affect the fabric quality as startup marks and differential dye take up are appeared on the fabric as defects. The ambient conditions in the vicinity of the weaving machine is subjected to vary over the day due to the heat dissipation from weaving machines and many other reasons such as sunlight and prevailing weather conditions. In the weaving preparational process, warps ends are generally sized so that they can withstand various stresses encountered in weaving process. However, weft yarn is not sized to retain greater flexibility and hence it is much susceptible for damages. The possibility of damaging the weft yarn is further influenced by the variations of surrounding conditions and hence these conditions are much sensitive for the weft yarn breakages during weaving process. In this paper, authors attempted to analyze the effect of surrounding conditions to weft breakages in weaving and device an automatic in-line moisture control system for weft package in weaving machine. Based on the experimental evidences, authors verified the effectiveness of the automatic moisture control system and their strong industrial implication in existing weaving machines

Mathematical modeling of weft yarn tension in pirn winding

Pirn winding is an operation of winding yarn from supply yarn package onto pirns which are used for shuttle weft insertion. Firm and coherent winding tension is required to maintain in the pirn winding process to withstand the high forces produced by the deceleration of the shuttle at the end of each pick and to avoid permanent strains in yarns which will appears as fabric defects in weaving. The package size and its diameter vary due to subsequent winding of pirns. Hence the balloon effect varies and caused to change the thread tension at the winding point of the pirn. The thread tension variation is considerably significant from the first pirn wound from a package to the last pirn wound from the same if no tension controlling mechanism is devised. Placing dead weights on the disc tension controller which adds a tension to take off tension may help to compensate the yarn tension variation to some extent to combat with this problem. However, this is a stepwise manual compensation technique which needs the correct timing of compensation to avoid significant tension variations in pirn windings. The author attempted to theoretically analyze the tension variation in the yarn path of the pirn winding machine and theoretically model the tension variation with and without deadweight placement on the tensioners. Author also verified the accuracy and the validity of the model developed through the experimental results obtained at different locations along the yarn path.

Measurement of seam puckering and influence of Its causes

Seam quality is very important aspect of any form of textile assembly using sewing. The quality of the seam is governed by the seam puckering, which mainly depends on the technological parameters of the sewing machine and fabric specifications. Though this dependency is known in qualitative aspect, very little researches have been focused to investigate the quantitative aspect of seam puckering behavior of the seams. The Phong's shading algorithm based luminosity model was developed to estimate the dimensional parameters from the image of the seam captured and, an investigation has been carried out to analyze the dimensional characteristics of puckered fabric using image processing techniques and neural networks. This objective assessment attempt goes beyond the replacement of conventional subjective puckering evaluation methods of seams and move towards the development of empirical models for the causal effects quantitatively. That is the determination of correct needle thread tension setting which is the most influential machine parameter for seam puckering, for a minimum puckering

Tension variation in sectional warping, pt. 1 : mathematical modeling of yarn tension in a creel

The warping process is one of the weaving preparation processes to produce weaver’s beams which uses on weaving machines to produce grey fabrics. In sectional warping several hundreds of yarn from supply packages placed on a creel are wound onto a sectional warping drum as sections and then beaming off all warp yarns from the drum to the warper's beam, which is used for fabric production with or without the subsequent process known as sizing. The uniform and even yarn tension in warping process is vital to produce high quality fabrics on looms with high efficiency. The authors attempted to theoretically interpret in terms of mathematical modeling the warp yarn tension in the yarn path of the creel with due consideration to various parameters in sectional warping. Further theoretically model the warp tension variation according to the geometrical position of the package on a sectional warping creel. This paper reports a study of tension variation of cotton yarn unwinding from the supply package up to the exit point of the creel of a Kakinoki sectional warping machine. Authors have developed a mathematical model to analyze tension variation within the warping creel for the packages with variable diameters at different positions. Based on the developed mathematical model, tension was calculated at various places along the yarn path

Design of a weft gripper system for required weft tension on rapier loom

In an existing rapier loom, when the rapier comes out from the shed, the tension of the weft yam changes before the reed reaches the fabric fell. Also in case of elastic yam, a certain length of the yam may retract due to the elastic nature of the yam. With the existing systems of rapier looms, weft yam tension cannot be controlled until the weft is interlaced into the fabric. Because of the above reasons the quality, selvage and appearance of the fabric could be impaired

A System for analysis, categorisation and grading of fabric defects using computer vision

Inspection of fabrics is a major consideration in fabric manufacture, as well as in manufacture of garments and other fabric-based goods. In this research, a computer-based system for objective assessment of fabric defects was designed with emphasis placed on fabric defects occurring in the Sri Lankan industry. Image processing techniques were used to analyse scanned images of the test fabric, compare it with an ideal sample, and identify defects according to pre-learnt rules. The information gathered was then used to grade the fabric, either by determining the frequency of defect occurrence or assigning points. A new classification method for common defects was designed, thereby facilitating grading according to commonly used grading systems. A coding system for defects was also designed to help report defects to the user. The fabric defects were classified and stored according to the developed classification method and coding system