Fryma Fabric Extension Tester TF143

Test principle

Stretching a specimen with standard dimensions involves applying a specified load. After observing the extension, the tension is released. Following the recovery of the unstressed specimen, the length is measured.

Test method

Clamp the test sample. By rotating the shaft in the back anti-clockwise, the moving clamp is moved back to stretch the sample, so the stretch rate can be read directly on the scale, and both knitted fabrics and woven fabrics scales can be read. By pressing the knob on the right side, the moving clamp can be returned back to its initial position quickly.

Test Procedure

1 See that the clamps are properly aligned and parallel.

Woven fabrics. Set the clamps with their inside edges 200±1mm (8±0.05 in) apart (L₁).

Knitted fabrics. Set the clamps with their inside edges 75±0.5 mm (3±002 in) apart (L₁).

2 Secure the specimen in the clamps, making sure it is flat and unstrqined. Make reference marks (lines) on the fabric against the inside edge of the clamps in the centre of the jaws, approximately 25 mm (1 in) long.

3 Gradually increase the load on the specimen to 3kg±5g or 6kg±5g within a period of 7.5±2.5s, (The load will normally be 3 kg. For certain fabrics, particularly elastic fabrics for which a test at high extension is required, a load of 6 kg may be used,) Maintain this load for 10±2 s and then reduce the load gradually within a period of 7.5±2.5s until the clamps are returned to their original position.

4 Immediately begin to re-apply the load to the specimen and measure the length of the specimen (L₂) 1 min after application of the full load. Within 10 s of making the measurement reduce the load as before, returning the clamips to their original position. Remove the specimen from the clamps, immediately place it on a flat, smooth surface, and, after a period of 1 min from the time when the jaws were returned to their original position, measure the distance between the outside edges of the reference marks (L₃). If the determination of residual extension after a longer period of relaxation is required, the distance between the reference marks shall be remeasured (L₄) after a total relaxation time of 30 min, L₂, L₃, and L₄ shall be measured to the nearest 1 mm (0.05 in).

NOTE When tests are made at right angles to the wale direction of well-knitted fabrics the results are invalid if laddering occurs. When elastomeric threads are laid-in, precautions should be taken to prevent slippage of these threads through the fabric.

Report Contents

The report shall state that the tests were made according to this British Standard and shall indicate which method of the test (i.e., for woven or for knitted fabrics) was used.

The following information shall be given:

(1) The load applied.

(2) The value of the mean extension of the fabric in each direction.

(3) The value of the mean residual extension of the fabric in each direction after 1 min relaxation.

(4) If required, the value of the mean residual extension after 30 min relaxation.

Considerations for testing tensile Properties of fabrics

The tensile properties of the fabric are not only related to the basic properties of the fabric, such as fiber strength, yarn line density, yarn count, and other basic properties but also related to the test conditions for testing the tensile properties of the fabric. For example, the length of the test specimen, the speed of the tensile test, and the holding method of the specimen have an obvious influence on the test results of the tensile properties of the fabric. The fabric tension tester provided by our company is simple and practical: The sample cutting template solves the sample length problem, the weights of the two 3KG ensure the stability of the tensile speed, the sample's clamping is firm and the error is smaller.

Calculation and expression of results

1 Calculate the arithmetic mean values of L₂, L₃ and of L₄( in each direction separately for the five specimens. These are denoted by L₂, L₃, and L₄, respectively.

2 Calculate the mean extension percent (E) for the fabric in each direction from the equation: E = 100(L₂ - L₁)/L₁.

3 Calculate the mean residual extension percent after 1 min (R₁) for the fabric in each direction from the equation: R₁ = 100(L₃ - L₁)/L₁.

4 If required, calculate the mean residual extension after 30 min (R₃₀) for the fabric in each direction from the equation: R₃₀ = 100 (L₄ - L₁)/L₁.

5 The mean values of E₁R₁ and R₃₀ shall be quoted to the nearest 1 %.

Fryma Extension tester is on sale, please contact us if you want to know more about how to operate it.

[contact-form-7 id="16355" title="Inquiry"]