How to test the tear strength of the fabric?

Test the toughness by the feel of the cut.

Some fabrics can be torn with a little force. For some customers who want the fabric to be fastness enough, they will ask the fabric manufacturer to strengthen the strength of the fabric. The tear strength and breaking strength of the fabric are related to the warp and weft density and the yarn count.

There is no way to compare very thin fabrics with very thick fabrics, ordinary people know that thick fabrics are not easy to tear, and the fabric can not reach the tear degree, which can only be achieved by finishing it, but when the tear degree is reached, the fabric feels hard, and the weight is also a common problem.

<> textile fabric strength test experiment is a common type of experiment done by textile enterprises, textile strength reflects the quality and tensile resistance of textiles to a certain extent, textile fabric tear strength test methods may exist according to different standards There may be different methods, standard group (Hong Kong) **** engineer to the current commonly used testing methods to analyze for you.

Test Steps:

1.The specimen is parked in a laboratory environment for more than 8 hours.

2.Use a cutter to intercept 4 or more samples in the warp and weft directions of the sample. Attention should be paid to the following when cutting samples:

The sample should be at least 150mm away from the edge of the material; The warp direction sample should be parallel to both sides of the material, with 2 cutting edges up and 2 down; The cut weft direction sample should be perpendicular to both sides of the material, with 2 cutting edges to the left and 2 to the right.

3.The two ends of the sample are clamped on the upper and lower fixtures of the tensile machine respectively, and it should be noted that the part of the sample exposed on the upper fixture and the part exposed on the lower fixture should be consistent; To keep the sample in the clamp vertical, not tilted to the side; Set the speed of the tensile machine to 200mm min.

4.Start the test button of the tensile machine to start the test, and record the maximum force value of the tensile machine when the tensile machine completely tears the sample apart.

5.Each specimen is tested at least 4 times, and the average is taken as the final result.

Notes:

If there is a large difference (more than 30%) in the test results of several samples, the sample needs to be re-cut for testing.

Result calculation or judgment:

1.If all 4 values are qualified, the average of the 4 values will be used as the final result.

2.If one of the 4 values is unqualified, two more samples should be cut for re-inspection, and if there are any more unqualified in the re-inspection, it will be judged to be unqualified, and the average value of each re-inspection unqualified value in the initial inspection will be used as the final result. If there is no failure in the re-inspection, the average of all values will be used as the final result.

3.If two or more of the 4 values are unqualified, it is judged to be unqualified, and the average of the non-conforming values is used as the final result.

There are 5 methods for testing the tear strength of garment fabrics, the determination of tear strength by impact pendulum method, the determination of tear strength of trouser specimens (single seams), the determination of tear strength of trapezoidal specimens, the determination of tear strength of tongue-shaped specimens (double seams), and the determination of tear strength of wing-shaped specimens (double seams). Test instruments: electronic strength tester, pendulum tear strength tester.

Adopt GB T

Legal analysis: the tearing strength of woven fabrics in the general national standard is implemented according to the technical requirements of the physical and chemical properties of GB T 21295 clothing, according to the 2007 version of the Naju Town, the strength requirements of general fabrics can reach more than 10 Ox, silk fabrics should reach more than 7 Ox, and for cotton fabrics when the quality per unit area is less than 140 grams per square meter, as long as it reaches 7 Ox.

Legal Basis: "Standardization Law of the People's Republic of China" Article 2 The standards mentioned in this law (including standard samples of Laling) refer to the technical requirements that need to be unified in the fields of agriculture, industry, service industry and social undertakings.

Standards include national standards, industry standards, local standards, group standards, and enterprise standards. National standards are divided into mandatory standards and recommended standards, and industry standards and local standards are recommended standards.

Mandatory standards must be enforced. The State encourages the adoption of recommended standards.

Summary. The tearing strength of the cloth needs to be torn The fabric tearing is also called tearing, and the local yarn of the fabric is subjected to a concentrated load to tear the fabric. Tearing of fabrics is a common and prone form of destruction.

Due to the particularity of the local force at the tear, the tear strength of the fabric is much smaller than its tensile fracture strength. At the same time, the tear strength index is the main quality index to measure the damage resistance of the fabric when it is subjected to local force during use. Other forms of mechanical failure of fabrics (breakage, abrasion, etc.) are often in the form of tearing as the final failure, and in order to improve the life of the fabric, it is necessary to study fabric tearing.

The strength of the cloth mass digging tear needs to tear the fabric, which is also called tearing, and the local yarn of the fabric is subjected to the load action of the collapsing core, which makes the fabric tear. Tearing of fabrics is a common and prone form of destruction. Due to the particularity of the local force at the tear, the tear strength of the fabric is much smaller than its tensile fracture strength.

The tear strength index at the beginning of the same game is the main quality index to measure the damage resistance of the fabric when it is subjected to local force during use. Other forms of mechanical failure of fabrics (breakage, abrasion, etc.) are often in the form of tearing as the final failure, and in order to improve the life of the fabric, it is necessary to study fabric tearing.

How to measure the tear of the cloth.

The pre-mortem test methods for fabric tear strength generally include: tongue-shaped sample method (double seam) method, trouser sample (single seam) method, trapezoidal sample method, wing-shaped sample (single seam) method, drop weight method, etc. For this reason, the commonly used methods are trouser specimen (single seam) method and Senhao pendulum method.

There is no standard. The tear strength and breaking strength of the fabric are related to the warp and weft density and the yarn count.

Warp and weft density is also called fabric density, warp density + weft density. The warp direction is the length of the fabric, that is, the direction perpendicular to the width. The weft direction is the width of the fabric, i.e. the direction parallel to the width.

The total number of warp threads in a piece of cloth of 1 square inch is called warp density, and the total number of weft yarns is called weft density.

The yarn count is the thickness of the yarn, and its expression methods include S, D, N, TEX, DTEX, etc. Specific fabrics use specific specifications, among which S and D are more commonly used.

According to the fabric attributes and grades, the first-class standard for worsted fabrics FZT24002-2006 combed woolen fabrics is 10N

In this way, depending on what kind of fabric it is, if it is wool (worsted products containing wool), the standard for tearing strength is 10N.

Part 1: Impact pendulum method for determining tear strength.

Range. This standard specifies the method for determining the tear strength of fabrics.

This standard applies to woven fabrics. It can also be applied to fabrics produced with other technologies.

This standard does not apply to woven elastic fabrics, knitted fabrics, and fabrics and sparse weaves with large warp and weft differences that may cause tear transfer.

Thing. 2 Reference Standards.

The provisions contained in the following standards constitute the provisions of this standard by reference in this standard. At the time of publication of this standard, the versions shown.

for effectiveness. All standards are subject to revision, and parties using this standard should use the latest version of the standard listed below.

GB 6529-86 Standard atmosphere for humidity control and testing of textiles.

GB 8170-87 Numerical Modification Rules.

Definition: This standard uses the following definitions.

1 Tear Force

The force required to extend the initial incision on the specimen under specified conditions'

Note: Tearing strength is to tear warp or weft yarn and are called "warp tear" and "weft tear" respectively

2 Length of tear

The distance from the beginning of the application of force to the end of the incision.

4 Principles. The specimen is fixed on the forceps, the specimen is cut through an incision, the pendulum at the position of maximum potential energy is released, and the movable forceps leave the fixed iron pliers.

, the specimen is torn along the direction of the incision, and the work done to tear a certain length of fabric is converted into tearing force.

Appendix C gives an example of shearing a specimen from a laboratory sample. Avoid creases, edges, and non-representative areas of the fabric.

Instrument General Provisions.

The instrument shall be regularly maintained and adjusted according to the manufacturer's instructions, and a brief description of the maintenance and adjustment of the instrument's functions is provided in Appendix A, 62 Pendulum.

The tester is a pendulum type, the specimen is clamped between two iron pliers, one is movable, the other is fixed on the frame, and the pendulum is made by gravity.

Attach a falling and moving plier to the pendulum, and the pendulum tears the specimen but does not contact the specimen during the test.

It mainly depends on how much tear fastness is required, and it is qualified when it is reached, which is generally expressed by n.