Various Terms Used in Knitting Technology

Course: Horizontal row of loops produced by adjacent needles in knitting cycle is called the course of the fabric. A course is a predominately horizontal raw of needle loops produced by adjacent needles during the same knitting cycle.

Wales: Vertical column of loops produced by same needle in knitting cycle is called the wales of the fabric. Number of vertical columns of loop of knitted fabrics is called wale.

Face Loop: If the legs of new loop are passes over the old loop is called face loop.

Back Loop: If the legs of new loop are passes under the old loop is called back loop.

Stitch Density: The term stitch density is frequently used in knitting instead of a linear measurement of courses or wales; it is the total number of needles loops in a square area measurement such as a square inch or three square centimeters.
It is expressed as: Course per inch x Wales per inch

Stitch Length: Length of one loop in the course direction express in mm.

Number of Needle: Machine Diameter x Machine Gauge x 3.1416

Cam: Cam is the specific path of needles to produce a specific type of fabric.

There are three types of cam used in circular knitting machine;
1.      Knit Cam
2.      Tuck Cam
3.      Miss Cam

Knit Cam: It moves the needle upward enough to clear the old loop receive the new yarn.

Tuck Cam: It moves the needle upward not enough to clear the old loop but receive the new yarn.

Miss Cam: It does not move the needle upward. The needles neither clear the old loop nor receive the new yarn.


Needle: A knitting needle or knitting pin is a tool in hand-knitting to produce knitted fabrics. They generally have a long shaft and taper at their end, but they are not nearly as sharp as sewing needles. Their purpose is two-fold. The long shaft holds the active (unsecured) stitches of the fabric, to prevent them from unraveling, whereas the tapered ends are used to form new stitches. 


Variables of Knitting Technology

In flat knitting, the fabric is usually turned after every row. However, in some versions of double knitting with two yarns and double-pointed knitting needles, the fabric may turn after every second row.

Knitting Variables
 - Yarn Count
 - Yarn Twist
 - Spinning System
 - Yarn Ply
 - Stitch Length
 - Yarn Tension
 - Take Down Tension
 - Machine Gauge

Classification of Knitting

Knitting is two types:

1. Warp Knitting
2. Weft Knitting

Weft Knitting is again two types:

1. Circular Knitting
2. Flat Knitting

Circular Knitting is again two types:

1. Single Jersey
2. Double Jersey


Warp and Weft Knitting

There are two major varieties of knitting: weft knitting and warp knitting. In the more common weft knitting, the Wales are perpendicular to the course of the yarn. In warp knitting, the wales and courses run roughly parallel. In weft knitting, the entire fabric may be produced from a single yarn, by adding stitches to each wale in turn, moving across the fabric as in a raster scan. By contrast, in warp knitting, one yarn is required for every wale. Since a typical piece of knitted fabric may have hundreds of wales, warp knitting is typically done by machine, whereas weft knitting is done by both hand and machine. Warp-knitted fabrics such as tricot and milanese are resistant to runs, and are commonly used in lingerie.



Maintenance of Knitting Machine

Knitting m/c needs to be maintained regularly for getting excellent performance of m/c and also maintain the proper quality of production. Maintenance for circular and flat bed knitting m/c is different.

There needed separate maintenance for different types of knitting machines.


Maintenance of Circular Knitting Machine:

1. Check out the m/c before starting the m/c.
2. Check out the yarn type, fabric type before starting the m/c.
3. Check out the fabric which is producing by the m/c.
4. Check out the m/c motor, belt, panel card.
5. Check out the m/c wheel.
6. Check out; is the roller pulling the produced fabric regularly?
7. Check out the fabric detector and needle detector.
8. Check the knot catcher.
9. If needle or sinker breaks, then submit the broken needle and take new one.
10. Remove the dust from the m/c.
11. Check out the m/c by Electrical and Mechanical operator.
12. Check the density of gear oil.
13. Input the new gear oil if finishes.


Maintenance of Flat Bed Knitting Machine:

1. Check out the m/c before starting the m/c.
2. Check out the yarn type, fabric type before starting the m/c.
3. Check out the fabric which is producing by the m/c.
4. Check the all automatic system of m/c.
5. Check the upper yarn of m/c.
6. Check the m/c needle.
7. Take care about needle marks, oil marks and oil spot.
8. Check the system when producing tipping collar.
9. Check the knit card, yarn count.
10. If needle breaks, submit the broken needle and take new one.


4 point system for detecting or calculating fabric faults

There need international standard quality inspection section in all knitting industry where the fabrics will be inspected by inspection m/c for detecting the faults and remark the fabric roll as grade A, B, C and R (Reject).

They are using 4 point system for detecting the fabric faults. There point and grade of fabric inspection are as below:
1. Up to 01 to 15 Point = “A” Class
2. Up to 16 to 20 Point = “B” Class
3. Up to 21 to 30 Point = “C” Class
4. More than  30 Point = “R” Class
(R=Reject)

N.B: Any Hole = 4 Point

Actual Grade Formula: Points*3302/Length (meter)*Width (inch)

Calculation Points/100 SQ. M = Total Points*39.37*100/Roll Length (m)*Actual Width (inch)

Fabric Faults in Grey Stage

Sometimes, there are some common types of faults appears in the grey fabrics although very good care is taken in production.

The common types of faults are as below:

1. Needle Broken
2. Patta
3. Lycra Out
4. Fly/Contam.
5. Needle Marks
6. Stars
7. Thick and Thin
8. Holes
9. Oil Line
10. Sinker Mark
11. Oil Spot
12. Slubs
13. Line Drop
14. Line Out

We will try to discuss about all of them one by one soon...

Different types of fabrics produced in Knit textile industry

1.      Single Jersey
30. 1*1 Rib
2.      F.F Lyc S/J
31. H.F 1*1 Lyc Rib
3.      H.F Lyc S/J
32. 1*1 Rib Polyester
4.      Slub S/J
33. 2*1 Rib
5.      Heavey S/J
34. 2*1 Lyc rib
6.      Single Lacost
35. Thermal Rib
7.      Lyc Single Lacost
36. Varicated Rib
8.      Double Lacost
37.Vericated (Recheli Rib)
9.      Lyc D/Lacost
38. Waffel
10. Single Lacost Polyester
39. Mini Waffel
11. S/J Polyester
40. Motor Bike
12. F.F Lyc S/J Polyester
41. P/Interlock
13. Double Lacost Polyester
42. Design Interlock
14. Double Pique
43. Interlock P.K
15. Honey Comb Pique
44. Lyc Interlock
16. Birds Eye S/Lacost
45. F.F Lyc Interlock
17. French-Terry
46. Shiny Interlock
18. Lycra French-Terry
47. Interlock Polyester
19. Cross Terry
48. Interlock Mesh
20. Mini Terry
49. Recheli Interlock
21. Lycra Mini Terry
50. Comfort Interlock (Mesh)
22. Lycra Cross Terry
51. Eyelet
23. Loop Back Terry
52. Mini Eyelet
24. Lycra Mini Terry Polyester
53. Mini Mesh
25. Lycra Cross Terry Polyester
54. Pin Mesh
26. Lycra French Terry Polyester
55. Pin Mesh
27. Fleece
56. Flat Back Rib
28. Cross Fleece
57. 5*3 Rib
29. Alt-Fm S/Lacost

Interstoff Apparels Ltd Bangladesh

Interstoff Apparels Ltd (IAL) is a famous composite textile industry in Bangladesh located at Chandura, Gazipur, Dhaka (knitting unit is located at Gohail Bari, Zirani Bazar, Dhaka). IAL is producing different types of knitted fabric with great excellence.

They are also performing dyeing, printing, finishing and garment manufacturing operation and supplying products to the International Buyers. Single jersey, Single locust, Rib, Interlock etc are common type fabric produced by IAL.

There are two types of knitting machine in IAL they are; Circular knitting m/c and Flat bed knitting m/c. The no. of circular knitting m/c is 54 and no. of flat bed knitting m/c is 28. All the knitting m/c’s are active and working with good performance.

Among the 54 circular knitting m/c’s they are from 5 different company as Fukahama, Terrot, Jumberca, Tien Yang and Wellknit and among 28 flat bed knitting m/c’s they are from different company like Protti Fashiontronix, Kauo heng, JY-LEH etc.

The dia and gauge of different circular knitting m/c are different like 20”/24G, 21”/24G, 22”/24G, 23”/24G, 24”/24G, 25”/24G, 26”/24G, 28”/24G, 30”/18G, 30”/24, 30”/32G, 32”/24G, 34”/24G, 36”/18, 36”/24G, 36”/18G, 36”/28G.

There are 5 Rib m/c (m/c no. 18, 25, 26, 53, 54), 1 Interlock m/c (m/c no. 28) and rest 48 m/c’s are single jersey. Among the 48 single jersey m/c there are 7 open width single jersey m/c, 2 Multi Feeder Jersey and 2 Engineering Stripper.

The open width single jersey m/c produces knitted fabric in open width but they can also be used to produce tubular knitted fabric by changing some simple mechanism.

IAL is using different types of yarn of different count for their production of different types of fabric. The common counts of yarns are 20, 22, 24, 26, 28, 30, 34, 40 etc. The yarns are different types in properties like carded, combed, CVC etc.

IAL is mainly producing different types of knitted fabrics such as Single Jersey, Single Locust (With and Without Lycra), Rib (1*1 and 2*2) (With and Without Lycra), Polo Pique, CVC Fleece, 100% Polyester Fabric, Grey Melange, Interlock etc.

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Report according to the year: 2012