Fabric tensile strength test:
Tensile strength of fabric:
When the stretching force (load) is applied to the
fabric, it begins to elongate. As the stretching force (load) increases
gradually, the elongation also increases. When the amount of stretching force
reaches a certain point, the fabric begins to break. Now we can say that the tensile strength of the fabric is the amount of
stretching force (load) at which the fabric begins to break when it comes under
stretching conditions. It is measured in Newtons, pounds, or kilogram-force. It depends upon the yarn strength, material type or
thread count per square inch of the fabric etc. The tensile strength of the
fabric is determined separately in the warp and weft direction.
Synthetic fabrics have better tensile strength than
natural fabrics.
The fabric made of fine and long-staple fibres poses
higher tensile strength than coarse and short fibres.
If the warp and the weft count of two fabrics are
same, then the fabric having more threads per square inch will give a higher
tensile strength.
Fabric tensile strength test:
There are two types of methods used for testing of
fabric tensile strength:
11 - Strip test
22 - Grab test
Strip test:
In this test, the full width of the specimen is
gripped between gripping jaws and stretched. The whole test is completed in
below steps:
Apparatus used:
11- Fabric tensile strength tester
22- Fabric swatch
33- Scissor
44- Marking pen
55- Magnifying glass
66- Marking template
77- Needle
Specimens preparation:
The fabric tensile strength is determined in warp
and weft direction separately.
First of all, the warp and weft direction of the
fabric is identified carefully with the help of magnifying glass.
Now, a number of specimens from warp and weft
directions are prepared according to the testing standard. 5 specimens from each direction are prepared.
In many testing standard procedures, the length of
the test specimen is kept 200 mm or 8 inches and the width of the specimen is
kept 50 mm or 2 inches.
The gripping margin is also taken in the length
direction according to the gripping jaws of the testing instrument.
The warp or weft threads of the specimens are aligned by removing the threads of edges of width sides with the help of a needle. You can see the below pictures:
Testing method:
First of all, the warp specimens are tested one by
one. The specimen is tightened between fixed and movable gripping jaws
carefully. please see the below picture:
The specimen length between both gripping jaws is
kept 200 mm accurately.
Now, the reading of the load cell is observed in
relaxed condition.
The power supply is switched on now.
The movable jaws begin to travel and they apply a
stretching force upon the specimen.
When the stretching force reaches a certain limit,
the specimen gets broken.
The breaking load is recorded automatically in the
load cell.
The breaking force is noted now.
The difference between the last reading and initial
reading is calculated.
This difference is the tensile strength of the fabric.
Grab test:
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