RU2311637C1 - Method of measurement of anisotropy of changes in linear sizes of fabrics at cutting - Google Patents

Abstract

FIELD: light industry.

SUBSTANCE: method can be used for studying mechanical properties of fabrics for measuring anisotropy of changes in linear sizes at cutting. Lines of cutting in form of ox-eye daisy flower with length of 200 mm from edge are marked in different directions, for example, at angles of 0°, 15°, 30°, 45°, 60°, 75°, 90° ...345 to longitudinal direction on the same sample made in form of circle with diameter of 500 +-1 mm. Sample is cut along marked lines by 200 mm from edges. Then sample is fixed onto disc table and linear sizes of cuts of fabric are measured in 30 minutes. Changes in lengths of cuts (CLCα, %) depending on direction (α) are used to judge on anisotropy of changes in linear sizes. Test conditions are brought closer to real conditions of cutting when producing items.

EFFECT: higher information truth of characteristics.

3 cl, 7 dwg, 1 tbl, 1 ex

Description

The invention relates to methods for investigating the mechanical properties of materials for garments and can be used in the garment industry and the domestic services sector to determine changes in the linear dimensions of fabrics in the process of processing them into garments.

There is a method according to OST 17-790-85 for determining changes in sample size under the influence of wet-heat treatment [1], but it does not allow to determine the change in the linear dimensions of the material during cutting (cutting) and does not give an idea of the anisotropy of changes in linear dimensions when cutting parts under different angles to the warp threads.

Closest to the claimed technical solution is the method of determining the anisotropy of drape of textile materials [2], selected as a prototype, by which the anisotropy of changes in linear dimensions under the influence of its own mass is determined, including the preparation and marking of samples of textile materials at different angles to the longitudinal direction, fixing the sample, measuring linear dimensions and determining the anisotropy of changes in linear dimensions.

The disadvantage of the prototype is the low information content, since only two slices are measured in the sample, because the sample is not cut along the intended lines.

The technical result of the claimed method is to simulate the real process of changing the linear dimensions of sections of parts during cutting (as a result of cutting), expanding the information content of the obtained characteristics due to information about the anisotropy of changes in linear dimensions during deformation of sections of parts of garments.

The method is as follows. Cut the sample in the form of a circle with a diameter of 500 ± 1 mm, mark the cutting lines in the form of “daisies” 200 mm long from the edge in various directions, for example, at angles 0 °, 15 °, 30 °, 45 °, 60 °, 75 °, 90 ° ... 345 ° to the longitudinal direction. The sample is cut along the designated lines 200 ± 1 mm from the edges. To fix the sample, a disk table with a diameter of 100 mm is used. After 30 minutes, the linear dimensions of all tissue sections are measured by any of the known measurement methods with an accuracy of 0.1 mm. Then the sample is removed, straightened on a horizontal plane and the linear dimensions of all sections are measured again.

Measurement of the sample in different directions of the slices allows us to determine the anisotropy of changes in linear dimensions. Indicators of changes in linear dimensions — elongation of slices (%) allow us to evaluate the technological features of the fabric, clarify the sizes of patterns when cutting in an oblique direction and perform adjustment of patterns, choose the necessary option for technological processing of the cut (planting, edge fixing).

The shape of the sample in the form of a circle makes it possible to determine the anisotropy of changes in linear dimensions and network angles from one sample, reducing the material consumption of the tests and bringing the test conditions closer to the actual conditions for cutting parts of garments.

Figure 1. Scheme for cutting and marking samples of test tissues.

Figure 2. Polar diagrams of the anisotropy of changes in the linear dimensions of pure-leaf plain weave fabric

a) on the device; b) on the plane.

Figure 3. Polar diagrams of the anisotropy of changes in the linear dimensions of pure twill weave

a) on the device; b) on the plane.

Figure 4. Polar diagrams of anisotropy of changes in the linear dimensions of finely crocheted weave (crepe)

a) on the device; b) on the plane.

An example of the method

As an example, the results of studying the anisotropy of changes in the linear dimensions of pure-leaf tissues of various weaves are given. On the test sample (figure 1) in the form of a circle with a diameter of 500 ± 1 mm, cut lines are marked in the shape of a "daisy" 200 mm long from the edge in various directions - at angles (α) corresponding to 0 °, 15 °, 30 °, 45 °, 60 °, 75 °, 90 ° ... 345 ° to the longitudinal direction, can withstand 24 hours in normal climatic conditions [3]. The sample is cut along the intended lines and fixed on a disk table. Undergoing the action of its own mass, there is an elongation of tissue sections and a change in network angles between the fabric threads.

After 30 minutes, the linear dimensions of all tissue sections are measured. Then the sample is removed, straightened on a horizontal plane and the linear dimensions of all sections are measured again:

ILR (α) = L _to -L ₀ / L ₀ · 100%,

where ILR (α) is the change in the linear dimensions of the tissue section in the direction α,

L ₀ - the initial length of the cut tissue

L _to - the final length of the cut tissue.

Tests of the sample in various directions make it possible to determine the anisotropy of changes in the linear dimensions of the fabric during cutting (cutting). Polar diagrams give a visual representation of the anisotropy of changes in the linear dimensions of the tissue (figure 2).

This information makes it possible to scientifically sound approach to the design of garments. The advantages of the invention are the approximation of the test conditions to the actual cutting conditions and the expansion of the information content of the characteristics due to information about the anisotropy of changes in the linear dimensions of the fabric.

Table 1 The change in the linear dimensions of the slices of tissue samples,% Cutting direction to warp, ° (degrees) Plain Weave Fabric Sample Twill Weave Shallow Weave Fabric Sample On the device On surface On the device On surface On the device On surface 0 0 0 0 0 0 0 fifteen 1,1 0.5 1.3 0.7 1,5 1,0 thirty 4.3 2,3 6.0 4.0 6.5 5,0 45 8.0 4.3 10.0 6.0 10.0 7.3 60 5,0 2.7 7.2 4.0 7.5 6.5 75 1,2 0.6 1.3 0.8 1.7 1.3 90 0 0 0 0 0 0 105 1,1 0.5 1.4 0.8 1,6 1,1 120 5,0 4.3 5,6 4.4 7.5 5.5 135 8.0 5,6 8.7 6.0 9.5 7.0 150 6.7 5,0 7.0 5,0 8.7 6.7 165 1,1 0.5 1,5 0.7 1,6 1,2 180 0 0 0 0 0 0 195 1.3 0.7 1.4 0.7 1.7 1,2 210 5.5 3.3 5.8 4.0 6.0 4.2 225 8.0 5,6 9.0 6.0 10.0 7.0 240 6.0 4.0 6.9 4.2 7.7 5.3 255 1,1 0.5 1.3 0.7 1.7 1,0 270 0 0 0 0 0 0 285 1,0 0.5 1.3 0.8 1,6 1,1 300 4.4 3.3 4.7 3,7 5.7 4.2 315 7.6 4.8 8.0 5.8 9.7 6.7 330 4.8 3.0 5.5 4.1 6.0 4.3 345 1,2 0.5 1,6 0.8 1,5 1,0

List of sources used

1. 0CT 17-790-85. Textile materials. A method for determining the change in linear dimensions after wet-heat treatment. - Instead of OST 17-790-78; enter 01/01/86. - M.: TSNIITEI, 1985 .-- 9 p.

2. Smirnova N.A., Ivanova O.V., Smirnov A.V., Serikova S.D., Tugunova E.I. A method for determining drape anisotropy. / RF patent №2255335 dated February 24, 2004.

3. GOST 10681 - 75. Textile materials. Climatic conditions for conditioning and testing of samples and methods for their determination.

Claims (3)

1. A method for determining the anisotropy of changes in linear dimensions during cutting (cutting) of tissues, including sample preparation, fixing and measuring the cut length, characterized in that the sample has a circle shape with a diameter of 500 ± 1 mm with marking in different directions, the sample is cut, the sample is secured on a round table with a diameter of 100 mm, measuring after 30 min the change in the length of the slices, and the anisotropy of changes in linear dimensions is judged by the change in the length of the slices (ILR _α ,%) depending on the direction (α). 2. The method according to claim 1, characterized in that the marking of the samples in the direction (α) is made at angles 0 °, 15 °, 30 °, 45 °, 60 °, 75 °, 90 ° ... 345 ° to the longitudinal direction . 3. The method according to claim 1, characterized in that the cutting of the samples is from the edge of the sample along the intended lines of 200 mm to obtain the form of "daisies".

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