GB/T 3903.41-2019 English PDF (GB/T3903.41-2019)

GB/T 3903.41-2019: Footwear - Test methods for uppers and lining - Flex resistance
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GB/T 3903.41-2019
Footwear - Test methods for uppers and lining - Flex resistance
ICS 61.060
Y78
National Standards of People's Republic of China
Replace GB/T 3903.41-2008
Footwear and lining test methods
(ISO 17694.2016, IDT)
Published on.2019-08-30
2020-03-01 implementation
State market supervision and administration
China National Standardization Administration issued
Foreword
This part is drafted in accordance with the rules given in GB/T 1.1-2009.
This part replaces GB/T 3903.41-2008 "Foot-resistant upper and lining test methods for folding performance", and GB/T 3903.41-
Compared to.2008, the main technical changes are as follows.
--- Revised the normative reference document (see Chapter 2, Chapter 2 of the.2008 edition);
--- Added the term "surface" (see 3.2);
--- Added an overview (see Chapter 4);
--- Added requirements for "wet test, low temperature test" in "Sampling and Environmental Regulation" (see 6.3 and 6.4);
--- Revised the number of tests the sample was removed from the machine (see 7.2.6, 6.2.7 for the.2008 version);
--- Revised the requirements for the recorded content of the coated material on the surface (see 7.2.8, 6.2.9 of the.2008 edition);
--- The test report has added requirements for the record "label" (see Chapter 8).
This section uses the translation method equivalent to ISO 17694.2016 "Footwear lining and lining test method folding performance".
The documents of our country that have a consistent correspondence with the international documents referenced in this part are as follows.
---GB/T 6682-2008 Analytical laboratory water specifications and test methods (ISO 3696.1987, MOD)
---GB/T 22049-2019 Standard environment for environmental conditioning and testing of footwear footwear and footwear components (ISO 18454.2018,
IDT)
---GB/T 22050-2008 Sampling position, preparation and environmental adjustment time of footwear samples and samples (ISO 17709.2004,
IDT)
---QB/T 2714-2005 Determination of the fastness to the physical and mechanical tests of leather (ISO 5402.2002, MOD)
Please note that some of the contents of this document may involve patents. The issuing organization of this document is not responsible for identifying these patents.
This part was proposed by the China Light Industry Federation.
This part is under the jurisdiction of the National Technical Committee for the Standardization of Footwear (SAC/TC305).
This section drafted by. Quanzhou Ryukyu Shoes Co., Ltd., China Leather Shoes Research Institute Co., Ltd.
The main drafters of this section. Yang Yumei, Qin Xiaobo, Chen Jingyi.
The previous versions of the standards replaced by this section are.
---GB/T 3903.41-2008.
Footwear and lining test methods
1 Scope
This part of GB/T 3903 specifies the test method for determining the folding resistance of the upper and the lining. The purpose is to evaluate the suitability of the end use.
Suitability.
This section applies to the upper faces and linings of various materials.
2 Normative references
The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article.
Pieces. For undated references, the latest edition (including all amendments) applies to this document.
ISO 3696 Analytical Laboratory Water Specifications and Test Methods (Waterforanalyticallaboratoryuse-Specification)
Andtestmethods)
ISO 5402-1.2011 Determination of the fastness of leather - Part 1 . Deflection method (Leather-Determinationofflex
resistance-Part 1. Flexometermethod)
ISO 17709 Sampling position, preparation and environmental conditioning time for footwear samples and specimens (Footwear-Samplinglocation,
Preparationanddurationofconditioningofsamplesandtestpieces)
ISO 18454 Standard environment for environmental conditioning and testing of footwear footwear and footwear components (Footwear-Standardatmospheres
Forconditioningandtestingoffootwearandcomponentsforfootwear)
3 Terms and definitions
The following terms and definitions apply to this document.
3.1
Flexibility resistance
The ability of the material to resist cracking or resist other damage at the crease.
3.2
Surface surface
The visible portion of the shoe material when wearing the shoe.
Note. The visible part of the material, for the upper surface, for example, the grained portion of the leather or the coated portion of the coated fabric, for the lining, the visible material inside the shoe
section.
4 Overview
The sample was cut from the upper or the shoe material, folded and clamped into the testing machine. Test simulates the damage caused by the inward bending of the upper, but not
It can better simulate the damage of outward bending. The test is carried out under wet, dry or low temperature conditions.
5 Test equipment and materials
The following test equipment and materials should be used.
5.1 Test machine, in accordance with ISO 5402-1.2011 (4.1) includes.
5.1.1 At least four pairs of clamps. The upper clamp consists of a pair of plates, see Figure 1. Lower clamp clamp fixed, perpendicular to the upper clamp
On the surface.
The unit is mm
Description.
1---bending angle 22°30'±0°30';
2---fixing clamp fastening screw;
3---fillet radius 2mm;
4---horizontal axis.
Figure 1 Upper clamp size
5.1.2 Upper clamp clamp, can swing back and forth, the swing angle is 22°30'±0°30'. The swing rate is (100 ± 5) r/min. Upper clamp
When the clamp is in the horizontal position, the distance between the upper and lower clamps is (25 ± 1) mm.
5.1.3 Counter, record the total number of swings.
5.2 Die cutter, size (70 ± 1) mm × (45 ± 1) mm, or use a similar tool for sampling.
5.3 Optical magnifying glass, the magnification is about 4 to 6 times.
5.4 For wet samples, the following instruments and materials are required.
5.4.1 Glassware, at least 100mm in diameter and 25mm in depth.
5.4.2 Distilled or deionized water shall comply with the requirements of Class 3 water in ISO 3696.
5.4.3 Filter paper.
5.4.4 Dryer, or other container that can be evacuated.
5.4.5 Vacuum pump, the dryer can be vacuumed to below 4kPa.
5.5 For the low temperature folding test, the freezer can keep the internal air temperature at (-5±2) °C, and the space inside the freezer is large enough to be placed.
Test equipment. If necessary, the temperature can be reduced to -30 °C.
6 Sampling and environmental conditioning
6.1 General
Use a die cutter to cut a specified number of rectangular specimens (see Table 1). The sample is equally divided into two groups, and the long side of one set of samples is parallel to the length of the material.
Direction of the direction (the leather is in the direction of the back ridge, the non-leather material is the warp direction or the machine extrusion direction), and the other set of specimens is perpendicular to the length of the material.
to. For sampling from the upper surface, the material length direction is the X-axis direction defined in ISO 17709.
For the upper surface, take a sample from the center of the front sill to ensure that the center of the specimen is the position where the shoe is most bent.
For sheets, samples are taken over the entire width and length available. For materials containing woven structures, avoid any two samples that are identical
Warp or weft.
For some types of shoes, especially children's shoes, it may not be possible to take large enough samples from the shoes. At this point, the width of the sample can be slightly reduced, but
The length (70 ± 1) mm should not be reduced. However, it is recommended to use raw materials for testing and, if necessary, to make holes and sutures on the specimen (or
He designed the features and the like to operate similarly to the front of the shoe.
Table 1 Standard test environment and number of samples
material type
Test environment
Dry state
Grain leather 2 2 -
Coated leather 2 2 2
Suede - 2 -
Coated fabric 4 - 4
Fabric 4 - -
6.2 Dry test
Prior to the test, all samples to be dry tested are placed in a standard environment in accordance with ISO 18454 for environmental conditioning, time
At least 24h.
6.3 Wet test
Place all samples to be wet tested in a glass dish. Inject distilled or deionized water to a depth of at least 10 mm. Glass
The dish is placed in a desiccator. Vacuum was applied until the pressure was less than 4 kPa and held for 2 min. Normal pressure was restored after 2 minutes. Repeat twice. From dry
The sample was taken out in the desiccator, excess water was removed by filter paper, and the wet test was started immediately.
6.4 Low temperature test
The test machine should be placed in a freezer. The sample was placed in a test machine. Close the door and start cooling until the desired temperature. Start after 30 minutes
test.
After the end of the folding test, slowly warm the freezer to room temperature to avoid the effects of condensation. Replace the sample and cool the freezer to the desired temperature.
After 30 minutes, he began to bend.
7 Test methods
7.1 Test principle
The rectangular sample was clamped into a folding tester. First, fold the surface inward and then clamp one end of the sample into the upper clamp to ensure
These surfaces are in contact and the fold line is horizontal. Then, the inside of the sample was folded outward by 90° and then clamped into the lower clamp. In the lower clamp, the sample
Folded, the fold line is vertical, and the sample is reversed or flesh-faced.
During the test, the clamp was oscillated at a constant rate and the specimen was repeatedly bent. At room temperature, dry or wet tests can be performed, or at zero degrees
Dry test is carried out. After the specified number of swings is reached, the test is stopped and the damage or salting out of the test is visually observed.
7.2 Test procedure
Mark the material direction on the back of each sample, such as an arrow, and determine the required test conditions.
It should be noted that the lining is facing down in the test and the upper side is facing up.
7.2.1 Test in a standard environment that meets ISO 18454 requirements.
7.2.2 If a wet test is performed, prepare the sample according to step 6.3.
7.2.3 If performing a low temperature test, follow the test in step 6.4. Ensure that the temperature of the air around the folding test machine meets the specified temperature (pass
Often -5 ° C ± 2 ° C).
7.2.4 Each sample is tested as follows.
7.2.4.1 Open the upper and lower clamp jaws at a distance of at least twice the thickness of the specimen.
7.2.4.2 Start the machine so that the lower edge of the upper clamp is parallel to the upper edge of the fixed lower clamp.
7.2.4.3 The surface is folded inwardly and the two long sides of the specimen are aligned. Place the folded sample and place one end of the sample against the appropriate fixture
The end of the clamp [see Figure 2a)].
7.2.4.4 Reverse the free end of the specimen along the upper clamp to make the opposite side or the flesh surface of the specimen [see Figure 2b)].
7.2.4.5 Clamp the free end of the specimen into the lower clamp [see Figure 2c)]. The sample folded here should be perpendicular to the lower clamp. Tighten the lower clamp
The clamp of the clamp ensures that the specimen is in a flat state and the specimen is not sagging near the upper clamp.
a) sample in the upper clamp p) b) sample folded in half c) fully clamped sample
Figure 2 Installation of the sample
7.2.5 Start the machine and stop the machine until the first inspection phase (see Table 2).
7.2.6 In addition to the conventional inspection stage, the wet sample shall be removed from the machine after every 5000 cycles, before the sample is re-wet according to step 6.3.
Assess the salting out situation.
Table 2 Appropriate inspection phase
Number of trials/secondary dry sample wet sample
1000 No is yes
2000 No Yes
5000 No is yes
10000 is yes
25000 Whether or not
50000 Whether or not
100000 whether or not
The inspection phase of each test depends on the type of material and the expected performance.
Note. For some applications, the flexion interval can be extended.
7.2.7 Stop the test and remove the sample. Use a naked eye and an optical magnifying glass (see 5.3) to assess the extent of flex damage. Check the specimen is folded
Whether there is any damage to the state of the Peace Show. Inspect the inward crease of each specimen (ie, the middle folded portion near the edge of the upper clamp) and record the damage
Happening. If the damage of the specimen to the clamped portion is caused by the wear of the clamp to the test, it is not within the recording range.
7.2.8 For materials with a surface coating, record.
a) whether the specimen has a slight or severe crease at the bend;
b) cracks - visible to the naked eye; fine cracks - visible to the optical magnifying glass;
c) material layer adhesion (eg between leather and finish);
d) whitening;
e) The coating is powdered or peeled off.
7.2.9 For fabrics. Record the breakage of the yarn (warp and weft).
7.2.10 For leather samples, the salting out condition is observed with the naked eye and classified into “slight”, “obvious” or “serious”.
7.2.11 Replace the specimen, place it in the same position, ignore any effects of permanent elongation, and start the folding test machine at the appropriate number of intervals (see
Table 2) Repeat the steps from 7.2.7 to 7.21.1.
8 test report
The test report should include the following.
a) For each sample record.
---label;
--- Wet test, dry test or low temperature test;
--- ambient temperature and corresponding humidity;
--- test direction and sample surface up or down;
--- the degree of flexural damage or the degree of salting out and the number of bends at each inspection stage;
--- Test the total number of bends.
b) If testing into shoes or forming uppers, describe the type of shoes, including commercial numbers.
c) Description of the test material, including commercial information (if known).
d) This part number.
e) Test date.
f) Any deviation from this test method.
GB/T 3903.41-2019
Footwear - Test methods for uppers and lining - Flex resistance ...