Thickness is an important property of a fabric that determines its warmth, weight, and stiffness. Thickness measurements are very sensitive to the pressure and sample size used in the measurement. This experiment we will determine thickness of carpet. Usually carpet is used as a floor cover. It is consists of an upper layer of pile attached to a baking. The pile is made from wool. Due to the scarcity of wool fiber, now-a-day, polypropylene, nylon or polyester fiber is used to make ply. Another cause behind the uses of synthetic fiber is, synthetic fiber is less expensive than wool. Carpet used not only for floor covering but also it is used in variety purpose. Such as: insulating a person’s feet from a cold tiles or concrete floor, making a room more comfortable as a place to sit on the floor, reducing sound from walking and adding decoration or color to a room.
Objectives:
To know about carpet fabric.
Come to learn how to measures thickness of carpet.
To know about Shirley thickness tester.
To know working principle of Shirley thickness tester.
Come to learn how to calculate the recovery percentage.
Principle of Fabric Thickness Test:
Engineers use calipers and screw micrometers to measure the thickness of machine parts but the textile technologist handles material which is readily compressed, therefore the instruments that are used textile engineer differ from other materials. According to B.S. 2544:1954, fabric thickness is measured as follow:
“Essentially, the determination of the thickness of a compressible material such as a textile fabric consists to the precise measurement of the distance between two plane parallel plates when they are separated by the cloth, a known arbitrary pressure between the plates begin applied and maintained. It is convenient to regard one of the plates as the presser foot and the other as the anvil.”
Standard testing temperature:
An atmosphere at the prevailing barometric pressure with a relative humidity of 65% and temperature of 200 C is called standard testing temperature.
Apparatus:
Shirley Thickness Tester.
Carpet as specimen.
Scissor
Scale.
Calculator.
Shirley Thickness Tester
Working Procedure:
At first, we will cut the specimen with scissor.
Then the prepared specimen is placed between anvil (E) and circular pressure foot (D). The specimen is kept under constant circular pressure. We need to use care when we place the specimen on the pressure foot. The specimen should not have any wrinkles in it.
Now the specified pressure is applied on the circular pressure foot by the pressure release lever.
A standard pressure of 100 grams per square centimeter is applied to the specimen.
When the circular pressure foot presses the specimen, the thickness of the fabric is measured with the help of a micrometer mounted in the tester.
All the test specimens are tested one by one as per the above mentioned method.
The means of all results is calculated. The fabric thickness is expressed in mm.
Calculation:
S/n
Adding load (gm)
Total load (gm)
Thickness (mm) after loading
Thickness (mm) after unloading
1
100 (dead wt.)
90
12.8
12.5
2
200
290
12.7
12.5
3
300
590
12.6
12.5
4
500
1090
12.5
12.4
5
1000
2090
12.4
12.3
6
1000
3090
12.3
12.2
Graphical Representation:
We can make a chart of loading and unloading on carpet thickness by placing the values of load or unload in Y axis and thickness in X axis. It is shown below:
For sample-1, Final result is compression of the carpet = 0.3 mm and recovery = 2.4%.
Precaution:
Specimens should be prepared accurately. The specimen’s size should be maintained according to recommended standards.
Pressure should be selected according to recommended standards.
Release the pressure lever gently.
It is very important to read the results carefully.
Leveling should be done correctly.
Conclusion:
From this experiment, we came to learn thickness test method of carpet. We also learnt working procedure of Shirley thickness tester. This experiment will help in our future life. Thanks to our teacher to help us.
References
Booth, J. (2008). Principles of Textile Testing. New Delhi: CBS Publishers & Distributors.
Corbman, B. P. (1983). Textiles Fiber to Fabric. New York: Mc Graw Hill.
HU, J. (2008). Fabric Testing. New York: Woodhead Publicatioing Limited.
Kazi Rashedul Islam is an “Assistant Technical Officer” at the Textile Engineering department at Jashore University of Science and Technology (JUST). He achieved his Bachelor of Science in Textile Engineering from Dhaka University of Engineering & Technology (DUET) in 2018. In 2012 he completed a Diploma in Textile Engineering degree from Begumgonj Textile Engineering College(TECN), Noakhali.
