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Choose to be at peace. Choose to see clearly with the eyes of love. Most of the technological methods used for manufacturing of textile products produce fibrous assemblies where the fibers are preferentially oriented in one particular direction. The fibers are often longitudinally arranged in the direction of the material output e. The cross-lapping technology in nonwovens arranges the fibers in the perpendicular direction to the direction of the material output. In other cases, the fibers are somehow oriented in the perpendicular direction to the direction of the material output e.
During the processing of fibrous assemblies, the fiber segments tend to take a direction near to the preferential direction, because they are mechanically affected by 1. Other fiber segments a adjacent segments of the same fiber, b segments of other fibers, and 2. Textile machine elements e. In fact, the influential actions of the surrounding fiber segments are different; therefore, it is necessary to represent a suitable simplified concept, which is able to express these different actions. If we consider that the fiber curvature is a smooth one, then the short fibers can be satisfactorily considered as fiber segment.
If a very short segment is cut from a very crumpled wire, it will be straight. The spikes are designated by y symbol in Fig. The concept of flexible belt and spikes 7 represent the action of the surrounding fiber segments. Let us take a fiber segment which is laying. Its initial point is located at the origin of the Cartesian coordinates, the end point is located at x0, y0 and a point below the end point of fiber segment lying on the flexible belt is designated by symbol. The direction of the fiber segment is defined by the orientation angle.
Let us now stretch the flexible belt in the direction of the shaded arrows direction? The fiber segment slips between the spikes of the belt, but it is still laying on the line p, which passes through the origin and the point. The coordinate x0 of point remains the same The lateral contraction of the imaginary belt is not considered , y0 is changed to a higher value y. This imagination has no direct relation with the spiked lattice found in textile machines. It is only an assisted imaginary representation, which simply simulates the surrounding actions on the fiber segments in other words, such representations facilitate easy modeling.
For example, in mechanical engineering, the elastic deformation is represented by the compression of a spring, which, in reality, is a completely different phenomenon. Due to the stretching of the imaginary flexible belt, the spikes will try to swing the fiber segment in such a manner that the segment will make an angle smaller to y-axis. According to Fig. Probability density function of fiber orientation in plane. Due to the mechanical actions of various machine elements, the very short infinitely short fiber segments in a fibrous assembly often change their orientation from their original purely random orientation to one defined preferential direction.
The original constant probability density f0 0 , according to Eq. The relative frequency of fiber segments black lines in this class is given by f0 0 d 0. The preferential orientation mechanism is now applied to the fiber segments that are lying in this elementary class. As a result of drafting, the whole elementary class is shifted to a new position and the angle 0 is changed to angle , the class width in this elementary class is also changed from the original value d 0 to d see the second dotted wedge in Fig.
The relative frequency of fiber segments in the elementary class after drafting is given by the expression f d. The relative frequency of fiber segments after drafting must be the same as those before drafting, because all of the fiber segments in the elementary class thick abscissas on the Fig. The behavior of the probability density function according to Eq. The parameter C corresponds to the drafting value of the imaginary belt considered in our present model. In actual process, the preferential orientation of fiber segments is governed by some other mechanisms.
Distribution function. The distribution function F of fiber orientation in plane is obtained from the integration of the probability density function expressed in Eq. Cauchys distribution of tangents. We consider that the random variable t has a probability density function 2 t. The relative frequency in this elementary class is 2 t dt. The relative frequency of both of them must be the same, because the same fibers belong to both the classes. Let us now consider two independent random variables x and y, where 1. Let us now find its probability density function. Note: This reminds us about the shooting practice as illustrated in Fig.
The distribution of values t can be considered as the distribution of tangents of angles , which is represented by the lines connecting the origin to each individual bullet. Generalized probability density function of fiber orientation in plane. Accordingly, the orientation angle to the y-axis is expressed as the summation of the preferential angle and another angle B, which is described by the angle that the fiber segments makes to the preferential direction as shown in Fig.
The probability density functions expressed by Eqs. It is evident that the angle was earlier used with the sense of the angle B; i. The probability density. Distribution of non-oriented angles of fibers. This angle is related to the original angle - shown in Fig. The probability density function of angle - is denoted by u - and it is of the same sense as the marginal probability density function u - , expressed in Eq.
Case study and experimental results. It is useful to study the orientation of fibers in a carded web, which is used for production of carded yarn or for production of non-wovens. There are several methods reported in literature to estimate the orientation of fibers in planar structures . One such method, known as a direct method e. A small quantity of black colored fibers is blended with white colored input fiber material, and a carded web is produced.
The samples of the web are put in-between two transparent disks glass, hard foil, etc. By applying a suitable immersion liquid for example, methyl-silicate is usually used for cellulose fibers , the noncolored fibers become glass transparent and the tracer fibers can be optically observed.
The curvature of fibers can be observed by means of image processing system, where the image of the fibers is digitized in a form of coordinates of many points. By means of a special software, the observed fibers are divided into many short fiber segments of length :l; the direction of each segment is determined and transferred to the respective class interval. The interval width is usually chosen as 5C. The histograms presented in Fig. Both carded webs are produced from viscose fibers, and are used for production of non-wovens.
The values of the parameters C and are obtained by applying a suitable statistical regression method, then those values are substituted into Eq. It is evident that there exists a very good agreement between the calculated and the observed values. The close values of C around 1. The small value of the angle can be explained by the error occurred during the measurements of the web in the longitudinal direction. It shows that the preferential longitudinal direction of relatively longer fiber segments is significantly noticeable.
The values of the parameters C and are also established and the probability density function is illustrated in Fig. This result should be understood as an empirical only as the lengths of the fiber segment chosen are different. It can be seen that the increase in the. Fibers are of 3. A fiber shown in Fig. Its macro-trend follows the preferential direction but its micro-shape is full of loops, waves, etc. Therefore, the short fiber segments, whose orientation is illustrated by the set of short arrows, are dispersed to many directions whereas the directional orientation of longer fiber segments, marked by the longer arrows, strongly.
It means that the longer fiber segments correspond to a higher value of C and vice-versa. Coefficient k n. Substituting the expression for the probability density function u - as stated in Eq. Distribution of the angle - of intersected fiber segments. Substituting the expression for the probability density function u - from Eq. If the orientation of fiber segments is purely random, i. Then, by using Eqs. The analytical integration is little complicated. The step-by-step integration is reported in Appendix A1. Note: Compare the behavior of this expression with that expressed in Eq.
Further, substituting the expression for the probability density function u - from Eq. Furthermore, substituting the expression for the probability density function u - from Eq. Graphical illustration. Let us cut the web in such a manner that the. The probability density function u - of non-oriented angles - can be calculated from Eq. The behavior of the calculated probability densities is shown in Figs. It is obvious from the previous example that the orientation of fiber segments in the whole fibrous assembly differs significantly from the orientation of fiber segments in a section of the fibrous assembly.
Note: The similar behavior can also be obtained for the negative values of angle. Number of sectioned fibers per unit sectional length. Compare this with Fig. The thick lines determine an areal unit whose volume is h. The mass per unit area areal weight G is expressed as follows. Note: The quantity kn depends on the angle as stated in Eq. Method intersecting method is derived and described in Ref. Nonwoven fleece. The nonwoven fleeces are usually produced by layering of webs of fibers as illustrated in Fig. Let us assume that the preferential direction of the fibers in the webs follows the technological direction of the production machine.
The probability density function of orientation angle related to y-axis of fibers in the web with preferential direction 1 can be expressed as follows. Similarly, the probability density function of orientation angle related to the y-axis of fibers in the web with preferential direction 2 can be expressed as follows g2. Then, the following expression if valid to write for the probability density function of orientation angle related to the y-axis of fibers in the web with preferential direction 2 g2. Evidently, the one half of the webs in the fleece follows the preferential direction 1 and the other half of the webs in the fleece follows the.
The value of E can also be determined by the following way. Let us consider that the areal densities mass per unit area of the web and the fleece are denoted by mw and mf respectively, and the widths of the web and the fleece are indicated by hw and a, respectively. The area occupied by the rectangular fleece, shown in Fig.
The thick zig-zag line, shown in Fig. The two adjacent dotted lines, comprising a web of length b, represent a repeat unit of the fleece and the number of such units present in the rectangular fleece is taken as n. It is evident from Fig. Also, it is evident from Fig. This expression can be used to find out the value of angle E.
Case study. A real nonwoven fleece, made up of polyester fibers of 0. A sample of this fleece was placed on a mirror, and the light was allowed to pass through the fleece and reflect off the mirror surface vertically back to the camera. The fibers, regardless of their position within the fleece, could merely block the light, appeared dark, and were in focus.
The result was an image with excellent contrast and uniformity. The image was thresholded to separate the fibers from the black and white background to obtain a binary image. This binary image was then analyzed to determine the orientation of fixed pixel fiber segments. Thirty such images were taken randomly from different parts of the fleece, thus the orientation of fiber segments was determined. This large set of orientation data was summarized by frequency distribution in 10 classes each of 18 degree width. The resulting histogram is displayed in Fig. The continuous line corresponds to the probability density function of fiber orientation in fleece as expressed by Eq.
Evi de nl ty, th e th eo re ti ca l re su lt corresponded well to the experimental one. Sliver is considered to be a linear fibrous assembly which is required to prepare staple fiber yarns. The orientation of fibers in the slivers is known to be a very useful parameter for evaluating the effectiveness of the fibre preparation processes namely, carding process and drawing process. Also, the fiber orientation is known to determine the fiber length utilization in the slivers.
But, the measurement of fiber orientation in the slivers is a very complex task as the cross-section of a sliver typically contains several thousands of fibers. One of the methods of ascertaining fiber orientation in the slivers is a direct method of measurement of inclination of the fibers to the axis of the slivers, using a fluorescent tracer fiber technique used by Morton and Summers .
The other is an indirect method, developed by Lindsley , based on the weighing of suitable combed-out and cut-out fringes using a special apparatus and evaluating fiber orientation in terms of some empirical ratios of fringe weights namely cutting ratio, combing ratio, fiber orientation index, and projected mean fiber length.
This method has been found to be widely followed in practice for evaluation of fiber orientation in the carded and the drawn slivers. Later on, Simpson and Patureau  modified Lindslays apparatus to measure and evaluate the orientation of fibers in the slivers more accurately and comprehensively. Using Lindsleys apparatus and methodology a larger number of research studies were conducted to characterize the orientation of fibers in the carded and drawn slivers and also to establish the effect of carding and drawing process parameters on the fiber orientation in the slivers .
However, Lindsleys methodology for evaluation of fiber orientation in the slivers has been understood as empirical only. In order to understand Lindsleys. Lindsleys methodology. Lindsley developed an apparatus which is schematically shown in Fig. The orientation of fibers in the slivers can be evaluated by using this appratus. The step-by-step procedure of evaluation of fiber orientation in slivers based on Lindsleys methodology is described hereunder. Step 1: Take a sufficiently long sliver. Twist one end of the sliver slightly so as to mark the direction by which it was delivered by the machine, i.
Take out the top three plates P, Q, R Figure 3. Step 2: Comb gently the sliver in the forward direction in order to remove all the loose fibers that are not clamped by the plates Q and D. Discard the combed-out fibers. Then cut the fibers using a sharp razor blade at the right edge of the plate Q and weigh the cut fiber portion. Let this weight be Wf.
The subscript f refers to the forward direction of the sliver. Step 3: Remove the top plate Q. Then, comb the fibers held below it. Retain the combed-out fiber portion and weigh it. Let this weight be Cf. Step 4: Put the top plate Q back to its original position. Then, cut all the fiber ends that are extending beyond the edge of the plate Q. Collect the cut fiber portion and weigh it. Let this weight be Ef. Step 5: Remove the plate Q again. Then, cut the fibers at the right edge of the plate R. Collect the cut fiber portion and weight it. Let this weight be Nf. Step 6: Repeat the steps from 1 to 5 for the backward direction.
Let the corresponding weights of fibers portions be Wb, Cb, Eb, and Nb, respectively. The subscript b refers to the backward direction of the sliver. Step 7: Repeat the steps from 1 to 6 for many samples of the sliver. Then, calculate the average of the weights. Modeling scheme. Let us now consider the following assumptions: 1 all fibers in the sliver have the same straight length l 10 and the same linear density fineness t, 2 all fibers have the same waviness so that the shorter crimped length a of each fiber is the same see Figure 3.
The random organization of the crimped fibers in the sliver is represented by the parallelograms as shown in Figs. Let us imagine that a part of such sliver is firmly gripped by a bottom plate and two top plates R and Q. The vertically shaded plate R permanently grips the sliver used, but the dotted plate Q is removed two times during the process of measurement.
We must think about the following three cases. Case 1 : The crimped fiber length a is longer than the width d of the top plate Q, Case 2 : The crimped fiber length a is shorter than the width d of the top plate Q, but the straight fiber length l is longer than d, Case 3 : The crimped fiber length a as well as the straight fiber length l is shorter than the width d of the top plate Q. Consider that the fibers protruding from the right-hand edge of the top dotted plate Q are combed as shown in Fig.
As a result, the fibers which were not gripped by the top and bottom plates are removed and the fibers which were gripped by the plates are straightened. The straightened fibers protruding from the right-hand edge of the top plate Q are then cut and the first fringe of fibers of weight W is thus obtained. In the next step, the top plate Q is removed and the rectangle of crimped fibers is seen to be lying under it see Fig. Let us imagine that we straighten all these fibers so that we obtain a wider rectangle of straight fibers as shown in Fig.
Of course, in reality, only the fibers protruding from the right-hand edge of the top plate R are straightened by combing, whereas the other fibers are combed out and contribute to the fringe weight C. Now the plate Q is replaced back on the straight fibers gripped by the The protruding fibers are then cut and a small fringe of fibers of weight E is thus obtained.
In the final step, the top plate Q is once again removed and the fibers protruding from the right-hand edge of the top plate R are observed as shown in Fig. The protruding fibers are then cut and a fringe of fibers of weight N is obtained. The commentary of the used procedure can be quite the same, only the shapes of the fringes are different Compare the corresponding schemes displayed in Figs. The commentary of the used procedure can also be quite the same.
We only notice another shape of the fringes and remark that the cut off fringe shown in Fig. It can be noted that the aforesaid step-by-step procedure can also be followed by putting another top plate P at the left-hand edge of the lefthand side top plate for backward direction of the sliver.
Fiber orientation. Each fiber is interpreted as a chain of small straight segments of constant lengths :l as shown in Fig. The projection of a segment in the direction of the axis of the sliver is denoted by the crimped length :a, and its non-oriented angle of inclination to the axis of the sliver is indicated by -. The last integral is also called as kn as described earlier in Eq. Using this, we can rewrite Eq.romanoguerra.com.br/179-dove-comprare-zithromax.php
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It is possible to derive the following expression for kn by substituting u - from Eq. The step-by-step derivation of the above equation is shown in Eq. If it is assumed that there are n number of fibers present in the crosssection of the sliver then the expression Eq. We use this equation also more generally; each crimped fiber length divided by the straightened fiber length is equal to kn in this model.
The detailed geometry of these fringes, introduced generally in Fig. The first fringe, earlier shown in Fig. Here, the number of fibers gripped along the clamping line BD of length y is equal to the total number n of fibers present in the cross-. This fringe of straight fibers has the triangular shape BCD with the longest fiber of length l. The second fringe, introduced in Fig. The fibers after straightening are shown by a set of horizontal lines; the continuous lines show the fibers gripped by the clamping line FG and the dashed lines show the fibers to be combed out.
The earlier position of edge of plate Q is marked by the thin dotted line BD. The oblique dash line AOD represents the ends of the fibers in the parallelogram of fibers before straightening of fibers, the dotted line OD represents it after straightening of fibers. The distance AB is equal to the crimped length a of fibers Compare it with Fig. The crimped length d plate width is elongated to the straight length d and we obtain the following equation valid similarly to Eq. Let the number of combed-out fibers be n1 and these fibers are lying at a distance y1, the remaining n2 fibers are lying at a distance y2.
By using of Eqs. Let us consider that the number of fibers held in the distance y3 is n3. It is then valid to write that. By using Eqs. The first fringe, introduced in Fig. This scheme is fully analogical to the scheme shown in Fig. Also, Eq. The length of the abscissa HJ is l d. Let us denote the length KH by y4 and the corresponding number of fibers be protruding beyond this length be n 4. The last fringe, after removing the plate Q, is shown in Fig.
The weight N of this fringe is equal to the weight F, derived earlier, minus the weight E of the triangular fringe KHJ. This is written below. In analogy to the previous discussion for obtaining Eq.
So, Eqs. Nevertheless, in this case, no one fiber is touching the edge BD after returning the top plate Q back to its original position. The last fringe obtained after removing the plate Q is shown in Fig. The weight N of this fringe is equal to the weight F of the fibers gripped by the plates along the edge FG. The results of weight of the fiber fringes derived earlier are summarized in Table 3. Generalization for fiber length distribution.
The model, derived for geometry and weights of fringes, assumes a constant length l of fibers and a constant value of the parameter kn. However, both of them are usually random quantities, hence they are generally described by a conjugate probability density function. Usually, we cannot find the variability of the parameter kn, but it is very easy to determine the distribution of fiber lengths. Therefore, let us keep the constant value of kn for all fibers, but think about the distribution of fiber lengths. Equation 3. Then it is valid to write the following expressions lmax.
The numeral subscripts in the brackets indicate the number of relevant equations, which correspond to Table 3. However, in practice, the integrands mentioned in Eqs. But, they can be solved numerically.
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The easiest of the approaches to solve them is stated below. Each partial sliver has the common length L and is created from fibers of constant length li. We assume in the original sliver are only the fibers of lengths l1, l2, Then each partial sliver will have values for Wi, Ci, Ei, and Ni according to the fiber length li see Table 3. The summation of each of these values for all partial slivers will give the. Practical example. A polyester drawn sliver of 5. The weight-based fiber length distribution of this sliver is shown in Table 3. The fineness of the polyester fiber was found to be 1.
The methodology as reported in mathematical model was followed to obtain the values of W, C, E, and N in the forward and the backward directions of the sliver. The average of one hundred such readings carried out on the aforementioned sliver is reported in the column named experimental in Table 3. The width of the plate d was kept at A computer program was developed to find out the corresponding values by using the equations derived earlier.
They are reported in the column named theoretical in Table 3. Theory of structure and mechanics of fibrous assemblies Table 3. Table 3. The coefficient of determination R2 was found to be 0. The theoretical results are found in good agreement with the experimental results. Let us mention that a set of experimental results of orientation of fibers in the carded viscose webs obtained by using the well-known tracer fiber technique was presented earlier in Section 3. It shows that the idea of transformation of fiber orientation from the web to the sliver without too significant change can be principally right.
By putting the values of C in Eq. As expected, the fibers are more anisotropically oriented in the forward direction as compared to the backward direction in the case of this drawn sliver. References Neck, B. Folgar, F. Orientation behaviour of fibres in concentrated suspensions, Journal of Reinforced Plastics and Composites, 3, Jackson, G. Mao, N. Anisotropic liquid absorption in homogeneous two-dimensional nonwoven structures, Journal of Applied Physics, 94, Murugan, R.
Design strategies of tissue engineering scaffolds with controlled fibre orientation, Tissue Engineering, 13, Pourdeyhimi, B. Theory of structure and mechanics of fibrous assemblies Pourdeyhimi, B. Blanc, R. Fibre orientation measurements in composite materials, Composites: Part A, 37, Komori, T. Estimation of fibre orientation and length in fibre assemblies, Textile Research Journal, 48, Fiber arrangement in card slivers, Journal of Textile Institute, 40, P Lindsley, C.
Measurement of fiber orientation, Textile Research Journal, 21, Simpson, J. A method and instrument for measuring fiber hooks and parallelization, Textile Research Journal, 40, Garde, A. Fiber configuration in sliver and roving and its effect on yarn quality, Textile Research Journal, 31, Rao, J. Theoretical computation of combing ratios of ideal and quasi-ideal slivers, Journal of Textile Institute, 53, TT Ghosh, G.
Studies on hook formation and cylinder loading on the cotton card, Textile Research Journal, 38, The effect of drawingframe variables on cotton fiber hooks and parallelization and processing performance, Textile Research Journal, 40, Perel, J. Characterization of fiber length in slivers, Textile Research Journal, 52, Ishtiaque, S. Impact of highspeed drawframe and its preparatory on fiber orientation parameters at sliver, Journal of Textile Institute, 98, Kumar, A. Measurements of fiber orientation parameters and effect of preparatory process on fiber orientation and properties, Indian Journal of Fiber and Textile Research, 33, Salhotra, K.
Analysis of spinning process using the Taguchi method. Part I: Effect of spinning process variables on fiber orientation and tenacities of sliver and roving, Journal of Textile Institute, 97, Das, D. Influence of carding and drawing processes on the orientation of fibers in slivers, Journal of Textile Institute, DOI: The fibers contact with each other in a fibrous assembly.
The region of contact, schematically shown by the dotted line in Fig. The place on fiber surface, which is in contact with other fiber, is called contact place. Hence, it is clear that one contact is created from two contact places. The number and position of mutual contacts among the fibers is known to influence the mechanical behavior of a fibrous assembly, for example, the mutual forces causing the deformation of a fibrous assembly are transmitting due to fiber-to-fiber contacts, etc. Basic idea of van Wyk model.
The simple textile fibrous assemblies are usually consisted of randomly oriented fibers. Therefore, the contacts between fibers also originate randomly. In contact places, some fibers try to be shifted to the place of other fibers while the other fibers resist this shifting. As the fibers cannot penetrate into each other, this process is ended with creation of fiber contacts. In an abstract sense, we can consider the fibers as geometrical bodies negligible mass or weightless , which can mutually penetrate into each other.
In such cases, the shifting of fibers will not end only with fiber contact, but they will penetrate into each other. In other words, the contact between fibers occurs in those places where the imaginatively geometrical fiber bodies together create a common penetration.
With this great idea, van Wyk  converted the problem of contact to a classical concept of intersections of bodies. Idealized fibers and their position in space. It is a fact that the geometry of fibers is very much complicated in a real fibrous assembly. The model. The location of each fiber in a three-dimensional space is given by its direction and position.
According to Section 3. The domain of fiber direction, i. Further, the coordinates of some definite point on a fiber express its position in a space. Such points can be, for example, one end-point of the fiber axis. Two fibers in a space. Let us now consider two fibers fiber No. Let us also consider that fiber No. Its direction is expressed by the unit orientation vector i 1, which is defined by the two spherical coordinates -1, 2 1. The coordinates of end point P shown in Fig. Fiber No. This fiber is randomly positioned in space.
For example, its position can be 2a or 2b, as shown in Fig. If we consider the fibers as geometrical weightless cylinders, then fiber No. In this case, both cylinders have a common intersection, as shown in Fig. Let us extend the end points P and S in the direction of vector i2 so that the abscissas PQ and SR of length l fiber length are formed. The angle B in the oblique prism corresponds to the angle between the orientation vectors i1 and i2.
If we express the scalar product of the vectors by the Cartesian coordinate system, we obtain the following expression for B. Note: So, the angle B is always a function of four variables -1, 21, -2, 22 only. Probability of fiber intersection. We think about the two weightless cylinders No. Machine operation and common structures produced with loop transfer. Color patterns in knitting.
Flat-bed and Circular knitting machines, comparison — similarities and differences. Common defects and corrective actions in knitting manufacturing. Manufacturing processes in knitting Industry. Mazza, P. Iyer, B. Mammel, W. Module Description Electrostatics. Module Description Chemical Thermodynamics. Gerasomov Ed. To implement certification and quality improvement techniques whenever it is required. To know and apply the rules and recommendations related to environmental protection. Distinctive technological characteristics of short and long staple fibrous materials.
Principles of conventional yarn spinning system processes. Blended yarn production elements. Spinning technology of continuous filaments processes, machinery. Design of yarn production. Problem solving of yarn production processing. Ltd, 3. Design operations. Presentation and development of patterns according to anthropometrics data. Patterns, Grading, fabric preparation and cutting procedures 6. Presentation of ready-garment production lines.
Presentation of sewing machine types, stitch types, and seam categories. Quality parameters of garment. Quality characteristics and finishing of garments. Promotion systems of trade, electronic commerce, internet. Total quality management systems. Procedures for Quality system certification. Laboratory 1. Body measurements and industrial sizes 3. Introduction to garment patterns 4. Flat pattern for skirts 5. Pattern grading 6.
Flat pattern for body vest 7. Introduction to Sawing machines 8. Types of Sawing machines and Stitches 9. Seam categories and special auxiliary equipment for sawing machines Sawing operations timing, production planning and control Auxiliary parts and finishing of garments Assessment Criteria 1. Pass Mark 5 min 1 - max 10 2. Eberle, H. Hermeling, M. Describe and identify the methods, select the structures and equipment of dyeing. Compute the parameters of equipment operation, examine the applications of advanced fibers. Compose new strategies of dye application, organize production and dyeing procedures.
Know and apply directives and regulations for environmental protection.
Module Description Radiation and color. Buxbaum, G. Fukuda, Z. Maekawa, T. Control arrays, Check box, Option button, Frame control. Multiple Forms and General Procedures, Debugging loops. Functions, Subs and Modules. Procedure scope. Global declarations and the Code Module. Menus and mouse events. Using Visual Basic to Create Graphics. Web applications and Visual Basic. Teaching notes. Conditioned probability. Independent events.
Random variables. Distributions: Discrete and continuous. Expected value, Variance. Statistics, Histograms, frequency polygons. Confidence Interval for the mean value. The knowledge and critical understanding to identify common mechanical machine parts. The knowledge and synthesis skills to analyze the stress state of each element. The knowledge to calculate the stress of each machine element under load. The knowledge and synthesis skills to select proper materials based on calculations. The knowledge to calculate and design mechanical parts 7. The knowledge of design norms and at the same time acquire technical perspective on constructions 8.
The knowledge of understanding technical drawing techniques that should be followed in order to complete a mechanical drawing 9. The knowledge of analyzing in drawing any component specifications. Module Description Theory 1. Introduction-General Instructions of module 2. Tolerances - Fittings 3. Calculation on Strength: Tension-Compression 4. Calculation on Strength: Torsion - Bending 5. Calculation on Strength: Buckling —Combined stresses 6. Screws 7.
Springs 8. Axles - Spindles 9. Fasteners Spindle hub Designing Views 3. Designing Section Views 4. Dimensioning 5. Intersection - Spreads 6. Drawing Reading 7. Numbering —Bill of materials BOM 8. Stergiou, I. Stergiou, MachineElementsI, SigchroniEkdotiki in Greek 2. Stergiou, Machine Elements II, SigchroniEkdotiki in Greek 3.
Boulgaris, Mechanical Drawing, SigchroniEkdotiki Publications in Greek 4. Papamitoukas, Mechanical Drawing, Knowledge and skills in the elements and the proper settings of the weaving machinery. To describe and identify the machinery used in the yarn preparation for the weaving process. Distinctive technological characteristics of yarns.
Principles of the weaving preparation systems. Conventional weaving preparation technology, machine standard settings and characteristics. Conventional weaving technology, machine standard settings and characteristics. Design of production in the preliminary processes. Exercises on the production processes.
Talavasek, V. Ltd, Lord, M. Distinctive technological characteristics of weft and warp knitting machines. Principles of conventional knitting procedures. Weft and warp knitting technology. Creation designs on weft and warp knitting machines. Set up a knitting machine to start production. Characteristics of knitted fabrics. Problem solving of knitting production -processing. Calculations concerning the formation of a shaped knitted fabric. Describe and identify the methods, select the structures and equipment of printing.
Explain the function of printing machines, assess their capabilities. Compose new strategies of digital printing, organize production and printing procedures. Compare batches, evaluate performance and efficiency of printing. Module Description Dyes and auxiliaries of printing. Kadolph, Ed. Bowles, C. Benn, L. Enterprise as an economic organization.
Components of data - environment - business types. Operating business —functions. Definition and Management content. Management Activities. Human resources. Control as special function. Total Quality Management. Programming personal time. Management career. The evaluation criteria for the work described in each case in the task assignment.
In-depth knowledge and critical understanding of the woven fabric production processes 2. Knowledge and skills of the particular aspects of the individual mechanisms of the weaving machines 4. Mechanisms for the weft insertion 2. Mechanisms for weft blending 3. Mechanisms for controlling warp and weft yarns 4. Principles of the woven fabric production systems 5. Non-conventional weaving technology processes, machinery, machine standard settings and characteristics 7. Parameters and woven fabric end-uses 8.
Design of woven fabric production Describe and identify the spectroscopic techniques, select the structures and equipment. Compose new management strategies, organize the quality control of dyeing. Module Description Kinetics of dyeing. Collier, H. Explain the capabilities of interactive technology, assess its prospects.
Compare methods and products of Finishing, evaluate the performance of interactive materials. Module Description Introduction to chemical and mechanical fabric finishing. Demir, H. Lacasse, W. Wulfhorst, T. Gries, D. Horrocks, S. Vincenzini, R. Knowledge and skills in the design of quality control systems in the textile industry 3. Knowledge and skills in the standardisation and optimisation of textile products.
Laboratory organisation and quality control design in modern spinning mills. Physical and mechanical properties and characteristics of yarns. Quality control case studies. BP Saville: Physical testing of textiles, Woodhead, 2. Definitions about Technology and Innovation, Discussion about the Scientific and Technological fields influencing the evolution of knitting technology 2. Taxonomy of the modern knitting technologies and the respective products and applications 3. Criteria for evaluating the technological level of knitting machinery 4.
Advances in Weft knitting technology 5. Seamless knitting 7. Knitting for special garments and sportswear 8. Knitting for Technical applications 9. Knitting for Medical applications Online monitoring systems in knitting shop floor Upon successful completion of this course the student will be able to: - know the trends of the clothing and the characteristics of each era and culture.
Module Description i. Basic concepts. Distinction between costumes of different eras. The phases and the key elements of designing different body shapes. Basic concepts and design principles. Chromatic harmonic combinations, contrasts and shapes. Methods of illustration, analysis and application of different techniques. Analysis of different techniques depicting patterns and textures of fabrics and garments.
Introduction to technical flat designing.
Basic flat design principles. Presentation of the work and critical analysis. Project Success Criteria. Carr, B. Describe and identify the methods of color difference determination. Compute the color optimization parameters, examine the combinability of dyes. Combine colorations and colored batches, develop and modify specifications for different dyes. Compose color fastness evaluation tests, organize color measurement models. Compare similar colorations, evaluate performance and efficiency of color prediction models. Module Description The course is an introduction to color science focusing on the applied aspects of color measurement.
Peters, Compute the parameters of electrospinning, examine its applications. Compose structures from nanofibers, organize their production and incorporation in fabrics. Compare various biomaterials, evaluate their performance and application. Module Description Introduction to polymeric biomaterials: Biomimetic, bioinspired nanomaterials; composite and self-assembled biomaterials.
In-depth knowledge and critical understanding of the various weaving designs used for the production of plain, multilayer and specialty fabrics 2. To describe and identify the various woven designs used in the woven fabric production. To explain the application of each design according to the fabric end-use. Display of designs, fabric appearance and drawing-in. Yarns, colour and weave effects used in warp and weft threads 5. To explain the operation of every machine in post-spinning yarn processes and non-conventional spinning processes for the production of specialty yarns and to calculate their operating parameters 3.
Principles and technologies of yarn post-spinning and fancy yarn system processes. Distinctive technological characteristics of the various types of fancy yarns. Distinctive technological characteristics of the various types of non-conventional yarns. Exercises on production processing. CA Lawrence: Advances in yarn spinning technology, Woodhead, 3. H Deussen: Rotor spinning technology, Schlafhorst Inc.
Describe and identify the transfer mechanisms, select between different heat exchangers. Compute the parameters of mass and heat transfer phenomena, examine the energy balance. Compose new energy strategies, organize industrial operation for energy saving. Module Description Laws of Thermodynamics. Zarzytci, A. Explain the function of equipment, assess the waste composition of a dyeing plant. Module Description Energy as an economic quantity.
Explain the general characteristics of polymers, assess their utility. Compare different synthetic fibers, evaluate the performance of their yarns.
Structure and mechanics of textile fibre assemblies / edited by P. Schwartz - Details - Trove
Module Description Introduction and basic concepts. Gupta, V. Presentation and development of knitwear design system M1 plus, Sintral 2. Applications for development of various projects in the knitting. Pretreatment controls the electronic knitting machine. Development and knitting basic designs in electronic knitting machine. Combinations of designs and loop structures for cost improvements knitting and garment. Effects of changing structures in the quality features of knitting. Development and manufacturing of intarsia knitting two, three and four colors. Development and manufacturing of intarsia knitting structures.
Development and manufacture knitwear with special performances. Assessment criteria for exams: Correctness of answer and precise correspondence to the question. Spencer J. Palling D. Raz S. They have to design fabrics and to create models using computer-based methods, to apply fabric on sketch. They should illustrate sample books by using several design programs. Additionally, designing sample patterns and generating the patterns for different size garments by using pattern design programs is a necessity.
Thus, they can evaluate the necessary sample book, to estimate the production cost of a garment and the wastage of fabric by simulating and organizing the cutting stage. To describe and identify the various ideal forms of the textile structures. To explain the mechanisms of most textile structures. Yarn geometry — ideal helix structure, linear density, specific volume, twist, twist angle, twist factor, yarn contraction due to twist - , packaging and arrangement of fibres into a yarn 2.
Fibre migration — mechanism, characteristics, tracer fibre technique. Elementary mechanics applied to bicomponent fibres and false-twist textured continuous filaments 5. Peirce theory on woven and knitted fabric geometry 6. Tear and elastic behavior of fabrics. Methods and techniques of analytical and computational yarn and fabric modelling. Choice of nets for computational modelling. Parametric computational representations of the three-dimensional structures J Hu: Structure and mechanics of woven fabrics, Woodhead, 8.
P Schwartz: Structure and mechanics of textile fibre assemblies, Woodhead, Arduino Lillypad Module Description Theory 1. Smart textiles, smart garments. Design principles. Production methods and applications. Microcapsules and applications 5. Optical fibers and applications 6. Piezoelectric materials. Energy harvesting in garments. Conductive textiles. Other smart materials. E-textiles and applications Textronics. Biometric systems. Athletic and Medical applications. Anthropometric systems.
Objective measurements. Customized Industrial production. Basic concepts and methodology of Multifunctional garments design 2. Introduction to Lilypad Arduino microcontroller and electrical components 5. Connecting Lilypad Arduino microcontroller in PC 6. Introduction to Arduino programming 7. Digital signals in Lilypad Arduino 8. Analogue signals in Lilypad Arduino 9. Study cases of advanced Arduino programming Working on and finalizing student Projects Ashby, K. McCann, D. Bryson, Smart clothes and wearable technology, 4.
Describe and identify the procedures, select the structures and equipment of bleaching. Explain the mechanism of bleaching, assess the reactivity of bleaching agents. Compose new bleaching methods, organize operation, factors and procedures of decoloration. Module Description Light and radiations. Sources of light.