The document discusses fabric tensile strength testing, defining tensile strength as the maximum load a material can support divided by its original cross-sectional area. It describes two modes of tensile testing machines: constant-rate-of-extension (CRE) and constant-rate-of-load (CRL), with CRE being the most commonly used. The document also outlines two testing methods, the strip test and the grab test, along with various factors that can affect tensile strength.

2. PRESENTED BY ……..

3. Topi
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Fabric Tensile Strength Test.

4.  Definition of Tensile Strength :
• Tensile strength is defined as a stress, which is measured as force
per unit area. Maximum load that a material can support without
fracture when being stretched, divided by the original cross -
sectional area of the material.

5.  MODES OF TENSILE TESTING MACHINE
There are two modes of tensile testing machine which are…
1. Constant- rate- of- extension (CRE)
2. Constant- rate- of- load (CRL)

6.  Constant- rate- of- extension (CRE) : Constant rate of extension is
the rate of increase of specimen length is uniform with time.
 Constant- rate- of- load (CRL) : Constant rate of load is the rate
of increase the load is uniform with time and the specimen is free
to elongate.
• The most commonly used mode is the CRE mode for tensile
strength test.

7.  Methods of measure Tensile Strength is…
• 1. STRIP TEST
• 2. GRAB TEST

8.  STRIP TEST :
• Sample size :
• Length = 8”
• Width = 2” (from 2.5” removing threads from both edges until the
width has been reduced to 2 inch).
• The specimen will be mounted centrally, securely gripped along the
full width to prevent slipping.
• The load is applied uniformly across the full specimen width.

10.  GRAB TEST :
• Sample size :
• Length = 6” (150 mm)
• Width = 4” (100 mm)
• Jaws width = 1” (25 mm)
• Gauge length = 3” (75 mm)
The speed is adjusted so that the sample is broken in 20 +/- second.

12.  Factors affecting the Tensile strength :
• 1. Number of test specimen.
• 2. Gauge length.
• 3. Extension rate.
• 4. Jaws or Grips.