Bursting Strength Tester TF142A/B

Terminology and definitions

Test area: refers to the area of the specimen in the ring gripper.

Bursting pressure or named pressure at burst: the maximum pressure applied to the specimen held together with the lower gasket diaphragm until the specimen bursts.

Bursting strength, also called strength at burst: the pressure obtained by subtracting the diaphragm pressure from the average bursting pressure.

Diaphragm pressure: the pressure applied to a diaphragm to achieve the average bursting expansion of a specimen in the absence of a specimen.

Bursting distension also named distension at burst: the degree of expansion of the specimen under the bursting pressure, shown in the form of the bursting height or bursting volume.

Height at burst:  the distance between the upper surface of the specimen before expansion and the top of the specimen at the bursting pressure.

volume at burst: the required liquid volume when it reaches the bursting pressure.

time to burst: the time when the fabric sample expands to burst out

Test principle

The specimen is clamped on the extendable diaphragm under which liquid pressure is applied so as to expand the diaphragm and the specimen. The volume of liquid will be increased at a constant rate until the specimen ruptures, and the bursting strength and bursting expansion can be measured.

The sampling

The sample should be taken in accordance with the standard of products or the relevant agreement. Folds, creases, fabric edges, or areas that are not representative of the fabric are not allowed to appear on the surface of the sample. The test can be carried out by working the clamping system without the requirement of cutting the sample generally.

Test procedure

Before the test, the sample should undergo conditioning in a relaxed state in accordance with related standards. During the test, keep the specimen in the specified conditioning and the atmosphere needed for the test.

Note 1: The test area should be 50c㎡ for most fabrics, especially knitted fabrics. However, the test area should be at least 100c㎡ for the fabric with low elongation based on the experience and pre-testing, such as the industrial fabrics.

Note 2: The comparative experiment should be carried out at the same increasing rate of the test area and the volume.

Set a constant volume growth rate at between 100 cm3/min and 500 cm㎡3/mimin. Or conduct a pre-test and adjust the bursting time of the test to 20s±5s.

Place the specimen on the diaphragm in a flat and tension-free state to avoid deformation in its plane. Clamp the specimen with the clamping ring to avoid damage and prevent it from slipping during the test. Adjust the dilatancy recording device to zero and tighten the safety cover according to the requirements of the instrument. Apply pressure to the specimen until it is destroyed.

Immediately reset the instrument after the destruction of the specimen, and then record the bursting pressure, bursting height or bursting volume. If the damaged area of the specimen is close to the edge of the clamping ring, the fact should be recorded.

Next repeat the test on different parts of the fabric. At least 5 test samples should be taken. If the buyer and seller make a consensus, the test sample can be increased.

Determination of Diaphragm Pressure

The diaphragm keeps expanding until it reaches the average bursting height or volume under the above-mentioned experimental condition.

Wetting test

In the wetting test, specimens should be impregnated in the water at third level with a temperature of 18 or 22℃. Take the specimen from the liquid and use the absorbent paper to absorb excess water.

Test report

In a test report, it is a must to display the general content and test result.

 General content

a) The number

b) Description of the specimen and sampling procedure (if required);

c) Model number of the expander.

d) Test area.

e) The rate of volume growth or swelling and breaking time.

f) The number of specimens, the damaged gripper, and discarded tests

g) The observation of swelling performance (e.g., one or two yarn directional damage)

h) The state of the specimen (conditioning or wet state)

i) Any deviation of the data.

Test results

a) Average swelling strength

b) Average swelling height.

c) Average swelling volume (if required).

d) Related coefficient of variation CV values (if in need);

e) Associated confidence intervals (if needed).