Basic Viva for Textile Engineers (Fibre related)

 

1.         What is Fiber?

          Ans: Fiber, which is either spun (or twisted) into yarn or else directly compressed into fabric.

2.         Define ‘Natural fibers’?

          Ans: Natural fibers that occur in nature can be classified as vegetable, animal,  and mineral.

3.         Define ‘Man made fibers’?

          Ans: The natural material of cellulose has been taken from cotton linters and wood pulp,             processed chemically, and changed in form and several other characteristics into fibers of various lengths.

4.         Define mineral fibers?

          Ans: Glass fibers are produced by combining silica sand, limestone, and certain other minerals.

5.         Define metallic fibers?

          Ans: Produced by mining and refining fibers such metals as aluminum, silver, and gold.

6.         Define rubber fibers?

          Ans: Made from the sap tapped from the rubber tree.

7.         Name animal fibers.

          Ans: Wool, Silk, mohair.

8.         Name re-generated cellulosic fibers.

          Ans: Rayon, Acetate, Triacetate, viscose.

9.         Name of some vegetable fibers.

          Ans: Cotton, linen, jute, hemp.

10.      Name of some mineral fibers.

          Ans: Glass, ceramic, carbon

11.      What is cotton fiber?

          Ans: The cotton fiber grows in the seedpod, or boll or the cotton plant. Cotton fibre is a                polymer of cellulose.

12.      What is linen fiber?

          Ans: Linen fiber is obtained from the stoke of the flax plant linen yarn can be very strong and lustrous and in used for apparel, have furnishings and upholstery.

13.      What is silk fiber?

          Ans: Is a fine continuous strand unwound from the cocoon of a moth caterpillar known as the silkworm. Silk is composed of protein. Lustrous, smooth, lightweight, strong, and elastic. Used for apparel home furnishings, and upholstery.

14.      What is nylon?

          Ans: Nylon is thermoplastic, resilient, elastic and very strong. It is used for a wide variety of apparel, have furnishings and industrials products.

15.      What is polyester?

          Ans: Polyester fibers are thermoplastic, they have good strength and are hydrophobic, do not absorb water well. Used for a wide variety of apparel, home furnishings, and industrial fabrics.

16.      Define spandex?

          Ans: Spandex fibers are extremely elastic. They are used for such purpose as foundation             garments, hosiery, swimwear and sportswear.

17.      What is the standard of cotton yarn count?

          Ans: The standard for the yarn count in cotton is I pound of fiber drawn out to make 840              yards of yarn. The resultant thickness or size is known as count number 1 or Ne1.

18.      What is ply yarns?

          Ans: Two or more strands or yarns are twisted together; they are designed as ply yarns.

19.      What is ASTM?

          Ans: American Society for Testing and Materials.

20.      What is ISO?

          Ans: International Organization for Standardization.

21.      What is ANSI?

          Ans: American National Standards Institute.

22.      What is the meaning of AFIS?

          Ans. Advanced fiber information system.

23.      What is ICS?

          Ans: Integrated Composite Spinning 84

24.      What do you mean by WIRA?

Ans. Wool International Research Association.

25.      How many fibers can you yield from each cotton seed?

          Ans: Each cottonseed may produce as many as 20,000 fibers on its surface, and a single ball         will contain around 150,000 fibers.

26.      Name some species of cotton

o    Ans: Gossypium harbaceum

o    Gossypium hirsutum

o    Gossypium peruvianum

o    Gossypium barbedense

27.      What is the Monomer of cotton

          Ans: cotton is made of cellulose and its monomer is glucose.

28.      Write down the moisture regain of cotton fibre?

          Ans. 8.5%

29.      The formula of cellulose.

Ans: C6H10O5

30.      The formula of glucose.

          Ans: C6H12O6

31.      What is viscose?

          Ans: Viscose is regenerated cellulose

32.      Natural fibres are hydrophilic in nature? (Yes/No)

          Ans. Yes.

33.      Manmade fiber are hydrophobic in nature(yes/no)?

          Ans. Yes.

34.      What are the long staple fiber?

          Ans. Jute, wool, flax, hemp.

35.      What is MR% of jute?

          Ans. 13.75

36.      What is MR% of viscose and silk?

          Ans. 11.0

37.      What is MC % of cotton?

          Ans. 7.834

38.      What is MR% of wool?

          Ans. 16.0

39.      What is MR% of nylon?

          Ans. 4.0

40.      What is MR% of polyester?

          Ans. 0.4

41.      Cotton is dissolved into 70% H2SO4(yes/no)?

          Ans. Yes

42.      Viscose is dissolved into 35% H2SO4(yes/no)?

          Ans. Yes

43.      Nylon is dissolved into 20% HCL/phenol(yes/no)?

          Ans. Yes

44.      Polyester is dissolved into 100% nitro benzene at 100℃ (yes/no)?

          Ans. Yes.

45.      Burning smell of cotton is like as burning paper(yes/no)?

          Ans. Yes.

46.      How polyester fibre form?

          Ans: To form polyester, dimethyl terephthalate is first reacted with ethylene glycol in the presence of a catalyst at a temperature of 302-410°F (150-210°C). The resulting chemical, a monomer (single, non-repeating molecule) alcohol, is combined with acid and raised to a temperature of 472°F (280°C). Newly-formed polyester, which is clear and molten, is extruded through a slot to form long ribbons.

Basic Viva for Textile Engineers (Spinning related) Part-1 1. What is yarn? Ans: Yarn is a long continuous length of interlocked fibers, suitable for use in the production of textiles, sewing, crocheting, knitting, weaving, embroidery, and rope making. 2. What is the first process/ machine in yarn production? Ans. Blow room. 3. What is the second process/ machine in yarn production? Ans. Carding machine. 4. What process / machine is used after carding? Ans. Draw frame. 5. What process is used after draw frame? Ans. Simplex. 6. What process is used after simplex? Ans. Ring frame. 7. What is the production of blow room? Ans. Lap. 8. What is the production of carding machine? Ans. Sliver. 9. What is the production of draw frame? Ans. Sliver/Drawing sliver 10. What is the production of simplex? Ans. Roving. 11. What is the production of ring frame? Ans. Yarn. 12. 1 lb(pound) to kg. Ans. 0.4536 kg = 453.6 gm = 16 ounce(oz). 13. What is the input of carding machine? Ans. Lap/Now chute feed system is being used. 14. What is the input of combing machine? Ans. Sliver lap. 15. What is the input of simplex? Ans. Drawn sliver. 16. What is the input of ring frame? Ans. Roving. 17. What is fiber fineness? Ans. Fineness is one of the most important parameter determining the yarn quality (Fine or Coarse). 18. How fineness is specified for cotton? Ans. Fineness is specified by micronaire value for cotton. 19. The maturity of cotton is defined in terms of the development of cell wall (Yes/no). Ans. Yes. 20. A fully mature fibre has a well developed thick cell-wall (Yes/no). Ans. Yes. 21. An immature fibre has a very thin cell-wall (Yes/no). Ans. Yes. 22. In mature fibre, dye absorption is high (yes/no) Ans. Yes 23. In immature fibre, dye absorption is low (yes/no). Ans. Yes 24. What is staple length? Ans. The average length of spinnable fibre is called staple length. 25. If staple length is increase then yarn quality is also increase (yes/no). Ans. Yes 26. Toughness of fibre has a direct effect on yarn and fibre strength (yes/no). Ans. Yes 27. If fibre strength is higher, then yarn and fabric strength is also higher (yes/ no). Ans. Yes 28. Short fibres deteriorate the yarn strength and uniformity (true/false). Ans. True. 29. What is the minimum strength for a textile fibre? Ans. Approximately 6 CN/tex (about 6km breaking length) 30. What do you know about Presley index =? Ans. Breaking load in Ibs/Bundle weight in mg.

 

1.         What is yarn?

Ans: Yarn is a long continuous length of interlocked fibers, suitable for use in the production of textiles, sewing, crocheting, knitting, weaving, embroidery, and rope making.

2.         What is the first process/ machine in yarn production?

Ans. Blow room.

3.         What is the second process/ machine in yarn production?

Ans. Carding machine.

4.         What process / machine is used after carding?

Ans. Draw frame.

5.         What process is used after draw frame?

Ans. Simplex.

6.         What process is used after simplex?

Ans. Ring frame.

7.         What is the production of blow room?

Ans. Lap.

8.         What is the production of carding machine?

Ans. Sliver.

9.         What is the production of draw frame?

Ans. Sliver/Drawing sliver

10.     What is the production of simplex?

Ans. Roving.

11.     What is the production of ring frame?

Ans. Yarn.

12.     1 lb(pound) to kg.

Ans. 0.4536 kg = 453.6 gm = 16 ounce(oz).

13.     What is the input of carding machine?

Ans. Lap/Now chute feed system is being used.

14.     What is the input of combing machine?

Ans. Sliver lap.

15.     What is the input of simplex?

Ans. Drawn sliver.

16.     What is the input of ring frame?

Ans. Roving.

17.     What is fiber fineness?

Ans. Fineness is one of the most important parameter determining the yarn quality (Fine or Coarse).

18.     How fineness is specified for cotton?

Ans. Fineness is specified by micronaire value for cotton.

19.     The maturity of cotton is defined in terms of the development of cell wall (Yes/no).

Ans. Yes.

20.     A fully mature fibre has a well developed thick cell-wall (Yes/no).

Ans. Yes.

21.     An immature fibre has a very thin cell-wall (Yes/no).

Ans. Yes.

22.     In mature fibre, dye absorption is high (yes/no)

Ans. Yes

23.     In immature fibre, dye absorption is low (yes/no).

Ans. Yes

24.     What is staple length?

Ans. The average length of spinnable fibre is called staple length.

25.     If staple length is increase then yarn quality is also increase (yes/no).

Ans. Yes

26.     Toughness of fibre has a direct effect on yarn and fibre strength (yes/no).

Ans. Yes

27.     If fibre strength is higher, then yarn and fabric strength is also higher (yes/ no).

Ans. Yes

28.     Short fibres deteriorate the yarn strength and uniformity (true/false).

Ans. True.

29.     What is the minimum strength for a textile fibre?

Ans. Approximately 6 CN/tex (about 6km breaking length)

30.     What do you know about Presley index =?

Ans. Breaking load in Ibs/Bundle weight in mg.

Basic Viva for Textile Engineers (Spinning related) Part-1

 

1.         What is yarn?

Ans: Yarn is a long continuous length of interlocked fibers, suitable for use in the production of textiles, sewing, crocheting, knitting, weaving, embroidery, and rope making.

2.         What is the first process/ machine in yarn production?

Ans. Blow room.

3.         What is the second process/ machine in yarn production?

Ans. Carding machine.

4.         What process / machine is used after carding?

Ans. Draw frame.

5.         What process is used after draw frame?

Ans. Simplex.

6.         What process is used after simplex?

Ans. Ring frame.

7.         What is the production of blow room?

Ans. Lap.

8.         What is the production of carding machine?

Ans. Sliver.

9.         What is the production of draw frame?

Ans. Sliver/Drawing sliver

10.     What is the production of simplex?

Ans. Roving.

11.     What is the production of ring frame?

Ans. Yarn.

12.     1 lb(pound) to kg.

Ans. 0.4536 kg = 453.6 gm = 16 ounce(oz).

13.     What is the input of carding machine?

Ans. Lap/Now chute feed system is being used.

14.     What is the input of combing machine?

Ans. Sliver lap.

15.     What is the input of simplex?

Ans. Drawn sliver.

16.     What is the input of ring frame?

Ans. Roving.

17.     What is fiber fineness?

Ans. Fineness is one of the most important parameter determining the yarn quality (Fine or Coarse).

18.     How fineness is specified for cotton?

Ans. Fineness is specified by micronaire value for cotton.

19.     The maturity of cotton is defined in terms of the development of cell wall (Yes/no).

Ans. Yes.

20.     A fully mature fibre has a well developed thick cell-wall (Yes/no).

Ans. Yes.

21.     An immature fibre has a very thin cell-wall (Yes/no).

Ans. Yes.

22.     In mature fibre, dye absorption is high (yes/no)

Ans. Yes

23.     In immature fibre, dye absorption is low (yes/no).

Ans. Yes

24.     What is staple length?

Ans. The average length of spinnable fibre is called staple length.

25.     If staple length is increase then yarn quality is also increase (yes/no).

Ans. Yes

26.     Toughness of fibre has a direct effect on yarn and fibre strength (yes/no).

Ans. Yes

27.     If fibre strength is higher, then yarn and fabric strength is also higher (yes/ no).

Ans. Yes

28.     Short fibres deteriorate the yarn strength and uniformity (true/false).

Ans. True.

29.     What is the minimum strength for a textile fibre?

Ans. Approximately 6 CN/tex (about 6km breaking length)

30.     What do you know about Presley index =?

Ans. Breaking load in Ibs/Bundle weight in mg.

Basic Viva for Textile Engineers (Spinning related) Part-2

 

30.   What is fibre elongation?

       Ans. Elongation is specified as a percentage of the starting length.

31.   What is bale management?

       Ans. Testing, sorting and mixing bales according to the properties of fibre for producing                specific good quality yarn at minimum cost is called bale management.

32.   When bale mixing is done?

       Ans. Before the blow room/Before the bales going into blow room.

33.   What is carding?

       Ans. Carding may be defined as the reduction of an entangled mass of fibre to a filmy web by working them between two closely spaced, relatively moving surface clothed with sharp wire points.

34.   Carding is called the heart/mother of spinning (true/ false).

       Ans. True.

35.   For cotton, higher the count, finer the yarn (yes/no).

       Ans. Yes.

36.   For jute, lower the count, finer the yarn (yes/ no).

       Ans. Yes.

37.   What is the name of combing waste?

       Ans. Noils.

38.   What is the meaning of TPI?

       Ans. Turns per Inch/Twist per inch

39.   What is the ring frame wastage?

       Ans. Pnewmafil, banda, sweep, hard waste.

40.   What is roving?

       Ans. A roving is a continuous slightly twisted strand of fibres which has not received its final drawing for yarn.

41.   Over twisted yarn become poor in strength (yes/ no).

       Ans.Yes

42.   What is the meaning of MIC?

       Ans. Microgram per inch.

43.   In direct system which one is fixed (mass/length)?

       Ans. Mass

44.   In indirect system which one is fixed (mass/length)?

       Ans. Length

45.   English count is denoted by Ne (yas/no)?

       Ans. Yes.

46.   Metric count is denoted by Nm(yes/no)?

       Ans. Yes

47.   Sliver and roving count is expressed by hank(yes/no)?

       Ans. Yes

48.   In spinning mill, up to roving the count value is expressed by hank then count (true/false)?

       Ans. True

49.   The shape of yarn become round due to twist (yas/no)?

       Ans. Yas

50.   How can you express fiber fineness?

       Ans. Weight per unit length.

51.   What is tensile strength?

       Ans. Tensile strength = force required to break the specimen/ cross sectional area

52.   What is yield point?

       Ans. The point up to which, a material contains its elasticity is called yield point.

53.   More fibre drawing produces more short fiber & resulted weak yarn (yes/no).

       Ans. Yes

54.   What is twist?

       Ans. Twist is the spirality of bundle of fibres/ filaments.

55.   Write down the types of yarn twist.

       Ans.“Z” Twist & “S” twist.

56.   Twist increases the strength of yarn (true/ false).

       Ans. True

57.   What is strain?

       Ans. Strain = elongation / initial length

58.   What is the unit of Strain?

       Ans. No unit.

59.   What is the meaning of CSP?

       Ans. Count Strength Product    CSP= Count × Strength