This is PPT file for basic knowledge in Sizing in manufacturing.

1. Seminar Guide :
Mr. K. G. Bhadada Sir
Presented By :
Aman Pandey
(19EMBTT202)

2. What is Sizing ?
 Sizing is the process of applying an adhesive coating
on the surface of the yarn.
SIZING M/C

3. Objective of Sizing :
 To protect the yarn from abrasion.
 To improve the breaking strength of the yarn.
 To increase smoothness of yarn.
 To decrease the generation of static electricity.
 To decrease hairiness.

4. Technological Changes Due To Sizing
1. Increase in breaking strength
2. Increase abrasion resistance
3. Increase in stiffness
4. Increase in elasticity
5. Increase frictional resistance
6. Increase yarn diameter
7. Decrease in extension
8. Decrease in electrostatic charge

5. Size Ingredients
 Adhesive
 Lubricant or Softener
 Antiseptic agent
 Deliquescent agent
 Weighting agent
 Anti foaming agent
 Wetting agent

6. Types of Sizing
1. Pure sizing ( Size pick up 3-10%)
2. Light sizing ( Size pick up 11-16%)
3. Medium sizing ( Size pick up 17-40%)
4. Heavy sizing ( Size pick up above 40%)

7. Development in Modern Sizing Machine
The essential components of a sizing machine to slash spun
warp yarns may be categorized as follows -
• Creels- unwinding zone
• Size boxes- sizing zone
• Drying cylinders- drying zone
• Bust rods- splitting zone
• Head stock- weaver’s beam preparation zone

8. Creels-unwinding zone
The major creel types housing multiple beams are:
• Over/under creel
• Equitension creel
• Inclined creel
• Vertical stack creel

9. Over/under Creels
Over/under creel for single size box
Over/under creel for two size boxes

10. Equitension creels :
Inclined creels :

11. Vertical stack creels
Vertical creels

12. Size boxes- sizing zone
This is the zone where the warp sheet is immersed into the
size paste and then squeezed under high pressure so that
uniform coating of size film forms over the yarn surface. The
process of immersion is called ‘dip’ and the process of
squeezing by means of a pair of squeezing rollers is called
‘nip’.

13. Important Parameters
The wet pick-up by the warp sheet is influenced by the following
parameters:-
 Viscosity of Size Paste :- Viscosity of a fluid indicates its
resistance against the flow. The viscosity of the size paste is mainly
influenced by the concentration (solid content) and temperature of
size paste. Higher concentration implies higher viscosity. Viscosity of
size paste reduces with the increase of temperature. The wet pick-up
generally increases with the increase in viscosity.
 Hardness of Top Squeeze Roll :- The bottom squeezing roller is
made up of stainless steel. The top squeezing roller is having a
metallic core part which is covered with synthetic material. If the
hardness of the top roller is low, then there will be flattening of the
roller. Thus the contact area increases which effectively reduces the
pressure acting at the nip zone. Therefore, the size pick-up increases.

14.  Squeezing Pressure :- The squeeze pressure forces out the excess
paste picked up by the warp sheet. Besides, the pressure distributes the
paste uniformly over the yarn surface and causes size penetration within
the yarn structure.

15.  Thickness of Synthetic Rubber on the Top Roller :- If the
thickness of synthetic rubber cover on the top roller is greater, then the
extent of flattening is more. This will reduce the nip pressure and thus
the wet pick-up will increase.

16.  Position of Immersion Roller :- The position of the immersion
roller within the size box is adjustable. If the height of immersion roller
is lowered then the residence time of the warp sheet within the size
paste increases. This will lead to the increase in wet pick-up if other
factors are constant.

17.  Speed of Sizing :-
Speed of sizing also influences the wet pick-up by the warp sheet.
 Higher speed reduces the residence time of the yarn within the paste
which should reduce the wet pick-up.
Higher speed increases the drag force between the warp sheet and size
paste which should induce more flow of paste with the warp sheet.
 Higher speed reduces the time of squeezing which should increase
the wet pick-up.

18. Some modern developments which is used in Sizing Box
Structured squeeze roller
:- The inlaid glass beads on the roller surface provide a special
structure which is maintained throughout the roller life. The
structured surface prevents the sticking of the threads and
results in reduced hairiness.
Size box heating
:- Two heating systems are matched optimally to one another.
The indirect heating in the double bottom compensates the
heat loss by radiation and the direct steam heating responds
quickly and effectively. High circulation and low liquor level
ensure an homogeneous liquor.

19. Equi-squeeze size box
:- A recent development is the Equi-Squeeze Size Box. In this system the
top squeeze roll position is adjustable. A unique bracket and loading
system allows the positioning of the roll to the rear 15 or 30 degrees off
the top center position, as shown in Fig. By moving the roll to the rear, the
adherence of yarns to the roll as they leave the squeezing nip is
minimized.

20. Liquor consumption
:- The liquor level in the size box is measured with a maintenance-
free sensor. This measurement serves to measure liquor
consumption and calculate the actual size pick-up.
Modern size box

21. Drying cylinders- drying zone
There are three principal types of drying methods used :
1.) Conduction drying (Cylinder dryer)
:- The conduction method is most commonly used, where multi-cylinder
drying is employed, as they are the most energy efficient.
The cans or cylinders are used in a multiple unit containing a series of
five, seven, nine, or eleven cylinders, usually arranged in two tiers to save
floor space.

22. 2.) Convection drying (Hot air dryer)
:- In this system, hot air is used as a drying medium instead
of the steam used in cylinder drying. The heated air is passed
through the drying chamber. The warp yarn through its
passage in the drying chamber comes into contact with the
heated air circulation.
Schematic of convection dryer.

23. 3.) Microwave Drying (Infrared Dryer)
:- These systems aim to conserve energy through the efficient and cost-
effective use of drying energy to replace conventional steam-based
conductive drying. Microwave radiation is an inexpensive form of energy
generation widely used in many industrial practices. Microwave energy
can be obtained easily without causing pollution and therefore receives
attention for the drying of textiles where large amounts of energy are
consumed.

24. Bust rods- splitting zone
After drying, the warp sheet is splitted so that the yarns
regain their individual identity before they are wound on
the weaver’s beam.

25. Head stock- weaver’s beam preparation zone
The final section of the machine is the headstock. This
consists of two small guide rollers and the main draw (drag)
roller as well as a unit to support weaver's beams of varying
widths. The warp sheet is guided around the draw roller as it
emerges from the comb.

26. It is then wound onto the weaver’s beam, the surface speed
of which is kept constant so the yarn can be wound at a
consistent tension from start to end of the beam. When the
required length of warp has been wound, the warp is cut
and a new empty weaver’s beam is positioned in its place to
continue the process until the desired number of beams has
been produced.