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1

New Geometrical Model of Woven Fabric Taking into Account the Change of Its Form, Size and Lateral Bending

Grechukhin A. P., Rudovskiy Pavel Hikolayevich

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 2 (146)

20--24

EN

This paper suggests a technique for the construction of fabric three-dimensional models based on the piecewise continuous representation of the thread surface. The approach allows to exclude such simulation defects as "interpenetration" of threads in the fabric, and takes into account the geometric features of the thread structure, the possibility of their bending in several planes, and changes in the form and sectional area. The geometric models obtained can be used to analyse the forces and deformations occurring in the fabric with the help of the finite-element simulation programs in various specialised software complexes, such as ANSYS, LS-DYNA, ABAQUS, NASTRAN etc. The structure parameters which are difficult to calculate using standard techniques, e.g. the pore volume and contact area between threads can be calculated with the help of describing the fabric three-dimensional structure.

PL

W artykule zaproponowano technikę konstrukcji trójwymiarowych modeli tkanin w oparciu o odcinkowo ciągłą reprezentację powierzchni nici. Podejście to pozwoliło wykluczyć defekty symulacyjne, takie jak „przenikanie się” nici w tkaninie, a także uwzględniło cechy geometryczne struktury nici, możliwość ich zginania w kilku płaszczyznach oraz zmiany kształtu i pola przekroju. Uzyskane modele geometryczne mogą być wykorzystane do analizy sił i odkształceń występujących w tkaninie za pomocą programów do symulacji elementów skończonych w różnych specjalistycznych kompleksach programowych, takich jak ANSYS, LS-DYNA, ABAQUS, NASTRAN itp. Ponadto parametry struktury, które są trudne do obliczenia przy użyciu standardowych technik, np. objętość porów i powierzchnia styku między nitkami mogą być z powodzeniem określone za pomocą zaproponowanej w pracy techniki konstrukcji trójwymiarowych modeli tkanin.

2

The Use of Fabrics to Improve the Acoustic Absorption: Influence of the Woven Fabric Thread Density Over a Nonwoven

Segura-Alcaraz P., Segura-Alcaraz J., Montava I., Bonet-Aracil M.

Autex Research Journal

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2018

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Vol. 18, no. 3

269--280

EN

Noise is frequently unnoticed, but it is one of the causes of unhealth for human beings reducing people’s quality of life. There are many materials that can be considered as acoustic absorbents. Textiles can be used to both improve the acoustic quality of and to decorate the room where they have been placed. In this study, we used some fabrics with 15, 20 and 30 ends/cm and 15, 20 and 30 picks/cm. The acoustic absorption coefficient was measured when the fabric was added as a resistive layer on top of a nonwoven made of polyester fiber. Results evidence that these fabrics can be efficiently used to modify the acoustic absorption of the nonwoven. Sound absorption coefficients measured via the impedance tube method show that these modifications occur. The results show how it is possible to improve the acoustic characteristics of a simple nonwoven to obtain sound absorption coefficients close to values of 1 at different frequencies by choosing a fabric with the appropriate combination of warp and weft count.

3

Analysis Possibilities of Controlled Transport of Moisture in Woven Fabrics

Sirková B., Moučková E.

Autex Research Journal

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2018

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Vol. 18, no. 4

385--391

EN

The article is focused on testing of selected properties of linear and planar textiles from modified cotton yarns. In this article, the influence of woven fabric construction on wettability and possibilities of detection of moisture in the woven fabric is analyzed. Improving the physiological and hygienic properties for woven fabrics can be achieved with a specially designed textile structure in combination with a permanent surface finish of sub-set of yarns. Inserting of hydrophilic and hydrophobic set of threads in the woven structure makes possible controlled water transport. Controlled transport of water ensures good clothing comfort. Using such woven fabric, accumulation of water on the skin does not occur during the process of thermoregulation of the human body. The properties and behavior of the designed fabric will be determined by surface finishing of the warp and weft yarns (sub-set of yarns), which are supporting elements of the fabric.

4

Weryfikacja wytycznych normowych dotyczących oznaczania zawartości części organicznych w gruntach organicznych metodą strat masy przy prażeniu

Maruta M., Straż G.

Przegląd Geologiczny

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2016

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Vol. 64, nr 11

918--924

EN

The key feature of organic soils is the acquaintance of organic matter content, which determines the possibility of their classification and possible usefulness for building purposes. Information included in Eurocode 7 (PN-EN 1997-1:2008; PN-EN 1997-2:2009), new classification standards (14688-1, 2:2006) and specifications (PKN-CENISO/TS 17892:2009) are general and do not specify which method should be applied to determine organic matter content. Therefore, the loss on ignition method according to the Polish standard (PN-B-04481:1988) is often used in Poland, although the standard guidelines are not precise enough, because the temperature range suggested for soil roasting is wide, from 600°C to 800°C, and the time recommended for sample roasting is 4 hours and additionally from 3 to 4 hours. The ambiguity of standard conditions for tests was the basis for undertaking research in order to verify the influence of leading parameters, i.e.: temperature and time, on the results of roasting. The tests were conducted on organic soil samples. A number of tests were conducted for temperatures, from 550°C to 850°C and for different time periods from 3 to 9 hours. In total, 756 samples were tested in 63 testing series. The test results revealed that the only main parameter to decide about the outcome of a roasting test is temperature. This, in turn, has a practical meaning, as it enables the test procedure to be facilitated and the roasting process to be shortened.

5

Application of MoldFlow Technology in the Warp Analysis

Liu J.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

99--101

EN

Warp analysis is always the key to the mold design. In practical process, it is always controlled by technicians through practical experience accumulation, which will lead to high waste. Through MoldFlow powerful analysis ability, a practical warp analysis is conducted, and then several plans are compared and adjusted, finally the best design is chosen. It simplifies the design process, improves design efficiency and decreases molding waste greatly, with strong practical application.

PL

Kluczem projektowania form wtryskowych jest zwykle analiza wypaczeń. W praktyce często oznacza to gromadzenie doświadczeń przez techników i jest bardzo kosztowne. Możliwość wykorzystania systemu MoldFlow do symulacji procesu wtryskiwania pozwoliła na praktyczne wprowadzenie analizy wypaczeń i porównania ich w różnych płaszczyznach oraz uzyskania najlepszego projektu formy. Zastosowanie MoldFlow upraszcza proces projektowania, poprawia jego wydajność i znacznie zmniejsza wypaczenia formy; ma bardzo duże praktyczne zastosowanie.

6

Study on the Dynamic Characteristics of Warp in the Process of Weaving

Shen D. F., Ye G. M.

Fibres & Textiles in Eastern Europe

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2013

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Vol. 21, no. 2 (98)

68--73

EN

The fluctuation process of warp movement is analysed by the nonlinear vibration method. Based on Newton’s Law, a differential equation of warp axial/cross direction movement is established. This paper separates the time variable from the space variable by the variable- separating method, then it gives a numerical solution of the motion equation by the fourth-order Runge-Kutta method. Also this paper discusses influencing factors and variable trends for warp vibration. Finally a method for the control of vibration is introduced.

PL

Proces drgań przy ruchu osnowy jest analizowany przez nieliniową metodę określania drgań. Równanie różniczkowe poprzecznego i osiowego kierunku ruchu osnowy oceniane jest na podstawie prawa Newtona. W pracy tej zmienna czasowa i zmienna przestrzenna rozdzielone są metodą rozdziału zmiennych, co daje rozwiązanie numeryczne równania ruchu przy pomocy metody Runge-Kutty 4-tego rzędu. W artykule omówiono również wpływ czynników i tendencji zmien na drgania osnowy, jak również przedstawiono metodę kontroli drgań.

7

Prediction of woven fabric properties using software ProTkaTex

Kolčavová-Sirková B., Mertová I.

Autex Research Journal

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2013

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Vol. 13, no. 1

11---16

EN

Fabric properties and fabric structure prediction are important in each industry domain. Generally all professional CAD packages for woven textiles system will be able to achieve basic fabric simulation and production output. A good CAD system should enable you to create design (dobby and jacquard woven fabric) ideas quickly and easily to enhance the way you work. The differences among competing systems fall mainly into the following categories: ease of use; speed of operation; flexibility of operation; advanced features; technical support; and ongoing software development. Computer simulation or prediction is oriented on standard woven fabrics, technical textiles, and composites. This article focuses on the presentation of software ProTkaTex and its use in the prediction of woven fabric properties. The software implements a generalized description of the internal structure of woven fabric on the unit cell level, integrated with mathematical models of the fabric relaxed state. User can calculate selected mechanical and end-use properties of dobby and jacquard woven fabric as well as can evaluate fabric behavior before real weaving. The major challenge is to develop software that industry will use in design centers for creation and development of new fabric structures for technical as well as clothing application.

8

Metoda tworzenia nowych bezsplotowych struktur tekstylnych

Kuchar M., Podsiedlik W., Słodowy J., Wiśniewski M.

Problemy Eksploatacji

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2011

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nr 4

195-206

PL

Przedstawiono realizację idei nowego systemu wytwarzania płaskich bezsplotowych wyrobów włókienniczych przy ciągłym ruchu organów wyko-nawczych urządzenia wytwórczego - bez tworzenia przesmyku. Brak splotu wyrobu tekstylnego uzyskano przez zaplatanie nitki wątkowej (rowingu szklanego z powłoką PCV) na wynoszonych lokalnie kołkach na obwodzie bębna pobierającego z ramy natykowej nitki osnowowe (takie same jak nitka wątkowa) i dociskanie nimi przez opasanie wątku do powierzchni bębna. Przewidziano konsolidację termiczną wyrobu płaskiego w postaci siatki budowlanej. Dla uzyskania postępu zaplatania rowingu wątkowego zaplanowano wysuwanie po jednej stronie bębna pojedynczego kołka, a po drugiej - dwóch jednocześnie. Jako mechanizm wodzący wątek przewidziano przekładnię cięgnową o stałej prędkości obwodowej z wodzikiem przymocowanym do cięgna. Wykonano projekt stanowiska badawczego do tworzenia bezsplotowych wyrobów płaskich składającego się z posadowionych na ramie następujących zespołów: - bębna z układem napędowym, - zespołu wodzenia nitki wątkowej, - zespołu odbioru wyrobu, - dwóch kulowych popychaczy obrotowych. Kulowe popychacze obrotowe realizują ruchy wynoszenia kołków, a napęd otrzymują od bębna - poprzez zazębienie kulek z wgłębieniami w czołach wysuwanych kołków. Zgłoszenie patentowe tego wynalazku (nr P.394865) zostało zarejestrowane w Urzędzie Patentowym RP. Wykonano część mechaniczną stanowiska badawczego oraz zbudowano na bazie sterowników PLC i falowników prądowych układy sterowania. Badania wytwarzania tekstylnych wyrobów bezsplotowych przeprowadzono wg planu ujmującego 2 rodzaje rowingu w osłonie PCV, prędkość obwodową bębna do 1,5 m/min, napięcie nitek do 80 N i temperatury podczas procesu zgrzewania do 600°C. Określono optymalne dla stanowiska badawczego parametry procesu wytwórczego. Uzyskany płaski bezsplotowy wyrób włókienniczy poddano ocenie geometrycznej (regularności podziałki siatki) i wytrzymałościowej. Stwierdzono pozytywne własności wytworzonego wyrobu bezsplotowego, wysoką wytrzymałość na rozrywanie i bardzo mały rozrzut wyników, co świadczy o dobrej powtarzalności procesu technologicznego.

EN

As the aim of work the realisation of the system of producing the new weaveless textile fabrics with the continuous movements of the generating elements of machine without forming the shed has been set. The performed actions involved: - Designing the test rig for production of the weaveless textile structures, - Production and verification of the test rig producing the weaveless textile structures, - Tests of the technological parameters for the producing the weaveless flat textile fabrics, - Identification of properties of the produced weaveless textile structures. The weaveless structure of the textile fabric has been made through wrapping the weft (the PCV covered glass roving) around the locally shifted pins that are assembled in the rings on sides of the drum, which takes out the warp threads (also the PCV covered glass rovings) from creel that press the weft thread to the surface of the drum. The weft and warp threads have been consolidated thermally to the fabric - a building grid. In order to achieve the progress in wrapping the weft thread its wrapping has been made on a single pin shifted on the one side of the drum and two pins moved on the opposite side. As a mechanism carrying the weft thread a roller chain transmission with a constant circumferential velocity, which has benn provided with a feeder, has been utilised. The design of a test rig for producing the weaveless textile fabrics has been made. The test rig consists of the following assemblies with their load-carrying structure: - Drum with is driving unit, - Weft feeding set with its driving unit, - Take-up set of the fabric, - Two ball rotating actuators. The ball rotating actuators realize the pins shifting. They are driven from the rotating drum - through their meshing with holes in pins. The patent application for this invention has been registered in the Patent Office of the Republic of Poland (No P.394865). The creel with its load-carrying structure with ball bearing systems and friction brakes has been designed. The test rig for the weaveless fabrics and creel have been produced in the Department of Textile Techniques of the Institute for Sustainable Techologies - National Research Institute. The control systems of the test device have been developed with usage of the PLC systems that govern: - The setting of the velocities of the drum and the feeder and synchronise the mutual position of these components, - The conditions of the thermal consolidation of the fabric. The test rig for generating the weaveless structures has been verified in the series of tests. A number of the design changes were introduced and as a result the proper action of thee rig has been achieved. The tests of the producing the weaveless textile fabrics have been performed according to the research plan involving 2 types of the PCV coated glass roving, the circumferential velocity of the main drum up to 1.5 m/min, tension of the threads up to 80 N and temperature of the thermal consolidation up to 600°C. The optimum parameters of the production process have been determined. The weaveless textile fabric has been tested for its geometric features (regularity of the grid) and its straight (tension tests) The good properties of the new fabric have been confirmed and very limited scatter of the test results has been shown, which demonstrates the good repatibilty of the production process.

9

Automatic Inspection of Woven Fabric Density of Solid Colour Fabric Density by the Hough Transform

Pan R., Gao W., Liu J., Wang H.

Fibres & Textiles in Eastern Europe

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2010

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Vol. 18, no. 4 (81)

46--51

EN

When analysing the colourcolours in woven fabrics images, the fabrics are suggested to be divided into three categories: solid colour fabrics, single-system-mélange colour fabrics and double-system-mélange colour fabrics. Corresponding to the classification, the inspection of woven fabric density can be also divided into three stages. A method of inspecting the density of solid colourcolour fabrics is discussed in detail in this study. The Hough transform is used to detect the skew angles of warp and weft yarns, and then the pixels in the fabric image are projected along the skew-direction. Warp and weft yarns can be segmented successfully by locating the true minimum values which indicate the interstices between the yarns. The density of solid colourcolour fabric can be inspected by counting the yarns in a unit length in the fabric image.

PL

Analizę kolorów w obrazach tkanin można podzielić na trzy kategorie: tkaniny jednobarwne oraz z jedno i dwu systemowego melanżu. Artykuł odnosi się do przypadku pierwszego. Do analizy obrazu zastosowano transformatę Hough’a. Położenie przędz osnowowych i wątkowych jest scharakteryzowane przez rzeczywiste odległości między nitkami oraz ilość nitek przypadających na jednostkę długości.

10

Shedding without dynamic warp loading. The possibility of forming a new woven structure

Szosland J.

Autex Research Journal

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2002

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Vol. 2, no. 1

38--45

EN

The shedding without dynamic warp loading is presented by a loom structure with the use of assembles of multi-angle shedding disks, e.g. quadrangular shedding disks and disks for increasing weft density. Several sets of these assembles form the rotating weaving drum, which is electronically controlled. The new machine loom, the multi-layer rotational weaving machine, allows the manufacture of completely new woven fabric structures, which until now was impossible to achieve with the use of conventional weaving machines. Woven fabrics can be manufactured with the use of warp and weft threads of extremely low tenacity, loose structure and strong developed surface, as can grid structures and woven structures with pile loop. The possibility to utilise unspinnable yarn, roving and selvedges was demonstrated on a model weaving machine specially constructed for the tests.

11

Behaviour of yarn interacted with high-speed object under sideways-constraint

Vu Hung D., Degrieck J., Van Langenhove L., Kiekens P.

Autex Research Journal

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2002

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Vol. 2, no. 1

46--56

EN

This paper presents an investigation of the dynamic behaviour of a yarn in an interaction with a high-speed object, for the lower warp sheet during the weaving process. The yarn movement on the object can be described in four stages from non-contact, contact, drop-off and withdrawal. A model is developed to predict this interaction, taking into account several factors such as yarn length, yarn tension, object speed, object orientation and object profile. A comparison of theoretical predictions and experimental measurements for different yarns indicates a good agreement. The theoretical model can be used to optimise the object profile in order to reduce the interactive yarn tension and to avoid any yarn damage.