List of top Textile Engineering and Fibre Science Questions on Yarn Manufacture, Structure and Properties asked in GATE TF

Polyester fibre is manufactured by the process of:
In plain weave fabric, the repeat size is:
The twist per inch (TPI) of a yarn primarily affects its:
The twist in a 36 Ne cotton yarn is 15 tpi. The twist multiplier (TM) in cotton system of the yarn (correct to 1 decimal place) is _________.
A woven fabric has weft yarn of 24 tex and pick density of 25 per cm. It is desired to replace only the weft with a 6 tex yarn of the same packing density. The pick density per cm required to keep the fabric cover the same (answer in integer) is _________.
The breaking strain of a yarn is 1.5. If the stress (\( \sigma \)) and the strain (\( \epsilon \)) of the yarn are related as, \( \sigma = 1.5 \epsilon^2 \), then the work factor of the yarn (rounded off to 2 decimal places) is:
In a tensile test, a 50 tex yarn specimen of 500 cm length extends by 10% at 600 cN. The length of the yarn after the removal of the load is 525 cm. The elastic recovery (%) of the yarn is:
The breaking strain of a yarn is 1.5. If the stress (\( \sigma \)) and the strain (\( \epsilon \)) of the yarn are related as, \( \sigma = 1.5 \epsilon^2 \), then the work factor of the yarn (rounded off to 2 decimal places) is:

Group I indicates type of spun yarns and group II indicates yarn characteristics. Match the yarns with their characteristics.


 

The twist in a 36 Ne cotton yarn is 15 tpi. The twist multiplier (TM) in cotton system of the yarn (correct to 1 decimal place) is _________.
A woven fabric has weft yarn of 24 tex and pick density of 25 per cm. It is desired to replace only the weft with a 6 tex yarn of the same packing density. The pick density per cm required to keep the fabric cover the same (answer in integer) is _________.
The parameter(s) required to convert load-elongation curve to stress-strain curve of a yarn is/are:
Cone winding machines equipped with electronic yarn clearers remove the following defect(s) from the spun yarn:
In a tensile test, a 50 tex yarn specimen of 500 cm length extends by 10% at 600 cN. The length of the yarn after the removal of the load is 525 cm. The elastic recovery (%) of the yarn is:
A parallel fibre strand of 30 tex count is coming out from the nip of the front delivery rollers of a ring spinning machine. This strand is given twist to produce a yarn such that the length of the yarn becomes 0.95 times the length of the parallel fibre strand. If 600 turns are present in 1 m length of the yarn, then the twist factor (tpm-tex0.5) of the yarn (rounded off to the nearest integer) is____
A winder operates at 750 m/min with 93% efficiency. The time (in minutes) taken for the winder to wind 1.2 kg of 20 tex yarn is approximately _______.
A ballistic type impact tester is shown below. The test specimen is connected to the bob of the pendulum of 10 N weight. The pendulum is released from a height of 1 m from the base, and this results in rupture of test specimen. Considering no frictional losses and neglecting the weight of the connecting rod, if the work of rupture of the specimen is 10 N-m, then the total swing angle (degree) that the pendulum makes during its travel (in integer) is
A ballistic type impact tester
Amongst the given options, the condition(s) which will increase the equilibrium wicking height of water in a yarn is/are
Group I lists yarn manufacturing technologies and Group II contains typical structural features of the yarns. Match the manufacturing technology with the structural features of the yarn.
Group I Group II
 P. Rotor spinning1. Twistless parallel fibres in core and helically arranged filament on surface
Q. Air-jet spinning 2. Helically twisted core and distinct wrappers on surface
R. Wrap spinning3. Multifilament core covered by staple fibres stuck to molten polymer
S. Bobtex spinning4. Twistless core wrapped regularly and helically by thin fibre ribbons
A cotton yarn of 20 tex count is replaced by a polyester yarn such that both the yarns have the same diameter and the same packing density. Assuming densities of cotton and polyester fibres as 1.52 g/cm\(^3\) and 1.38 g/cm\(^3\), respectively, the count (tex) of the polyester yarn (rounded off to 2 decimal places) is ________________.
A knitted fabric is prepared from a yarn of 15 tex count. The fabric has 16 courses/cm, 17 wales/cm and 2.6 mm loop length. The areal density (g/m\(^2\)) of the fabric (rounded off to the nearest integer) is ________________.
A square jammed plain cotton woven fabric is produced from 10 Ne yarn of circular cross-section. Assuming yarn density \(=0.91~\text{g/cm}^3\), find the number of threads per inch (rounded to the nearest integer).
In a guarded hot plate, the dimension of the square test plate is 15 cm $\times$ 15 cm. Keeping the temperatures of the test plate and the air at 35$^\circ$C and 20$^\circ$C, respectively, the power losses from the test plate with and without fabric specimen are 16 W and 40 W, respectively. The intrinsic transmittance [W/(m$^2$ K)] of the fabric (rounded off to 2 decimal places) is ...................
A 36 Ne ring spun yarn is produced from 1.2 Ne roving. The total draft and the break draft of the roving frame are 12 and 1.2, respectively. The diameters of back bottom roller, middle bottom roller and front bottom roller of the roving frame are 28 mm, 25 mm and 28 mm, respectively. If the middle bottom roller of the roving frame is eccentric, then the wavelength (m) of the periodic fault in the yarn, neglecting twist contraction, (rounded off to 2 decimal places) is ...................
A 30 tex cotton yarn is made into a lea of 120 yards for determining CSP. If the lea strength is 500 N, then the CSP of the yarn (rounded off to the nearest integer) is ...................