Sizing

1. SIZING

2. PREPARED BY ©right Name : MAZADUL HASAN SHESHIR ID: 2010000400008 Batch: 13th Batch (Session 2009-2013) Department: Wet Processing Technology Email: mazadulhasan@yahoo.com Blog: www. Textilelab.blogspot.com Southeast University Department of Textile Engineering

3. SIZING Introduction: Sizing is the process of applying an adhesive coating on the surface of the yarn. Sizing is applied into the yarn mainly to improve the weave ability of warp yarn by making it more resistant to action of weaving i.e. absorption, friction, tension & flexing. It also maintains good fabric quality by reducing hairiness, weakness & by increasing smoothness, absorbency of yarn. The most other features of the sizing is change of various physical properties. Sizing is applied on to the fibre surface by various process and various recipes according to the requirements. The most commonly used sizing machine is Slasher sizing machine. Sizing is the process of giving a protective coating on the warp yarn to minimize yarn breakage during weaving. Sizing is the most important operation in preparing warp yarn for weaving especially with cotton yarn. The smallest error in sizing process may be very harmful. This may increase warp breakage rate on the looms and consequently reduce weaving production and quality. Therefore sizing is termed as the “Heart of Weaving”.

4. Objects: 1. To increase the smoothness of the warp yarn. 2. To reduce hairiness of warp yarn. 3. To increase the strength of warp yarn. 4. In some cases sizing is now done to modify the character of the warp yarn. i.e. to have an effect on fabric weight on fabric weight, stiffness, handle properties etc. 5. To improve the weave ability of warp yarn. 6. To maintain good fabric quality by reducing hairiness, weakness and by increasing smoothness, strength of yarn. 7. To increase the tensile or breaking strength for cellulose yarn. 8. To increase the elasticity. 9. To remove the projecting fibers. 10. To reduce electrostatic formation for synthetic or blended yarn.

5. Requirement of sizing: 1. Sized warp must be strong and elastic. 2. Yarn strength and loss in elongation should be within admitted limits. 3. The process must ensure the applications of required amount of size on the yarn. 4. The tension of warp yarn must be constant all the time. 5. The weavers beam must have a cylindrical shape, necessary winding density and the yarn length. 6. The sizing process must be efficient, economical and must ensure the production of high quality size warps.

6. Sizing Process Involves:

7. Types of sizing: Types of sizing: Sizing may be classified into Four types on the basis of size% on the yarn. 1. Light Sizing :10% to 15%. 2. Pure Sizing :16% to 25%. 3. Medium Sizing:26% to 50%. 4. Heavy Sizing :50% to 100%.

8. Material/Chemical: 1. Adhesive. 2. Chemical. 3. Acrylic sizing agent. 4. Lubricant softener. Operation Staff: 1. PRODUCTION MANAGER. 2. SUPERVISOR OFFICER. 3. SIZER. 4. ASSISTANT SIZER. 5. HELPER.

9. Properties of Size Ingredient

10. What is Size take-up %

11. Different Technique Of Sizing

12. Recipe cooking: Recipe cooking: In the figure A is a motor; B is a agitator getting direct motion from motor. C is a mixing tank. Size ingredients are mixed with the help of agitator in mixing tank. Size ingredients are added in mixing tank by the help of inclined lid (H) & steam supply from steam pipe. After mixing size- ingredients passed through the valve (D) & then pumped by pump (E) into cooking & storing tank (G).

13. In the storing tank, steam is passed to maintain viscosity of size. Viscosities of size depend upon concentration & temperature of cooking tank (G). Before sizing is set to operate sizing liquor needs to be cooked, stored and transferred to the main m/c size box. Preparatory section in charge and/or sizing technologist gives the plan of size liquor quality and quality (recipe), considering the following factors:  Material to be sized i.e. yarn composition.  Diameter of material to be sized i.e. total number of ends.  Total weight of material to be sized. Size mixing man prepares the size liquor as per instruction and record in the production register. The preparing sequence is as follows:  Main switch at the main control panel is switch on.  Enter following set points for cooking process at the panel-  cooking temperature.  water quality.  cooking time.  Enter temp. set point for storage tank.  Open water valve with push button, water will come in.  When Agitator impeller is covered with water then switch on agitator with the push button.  Change with size powder, liquid size component etc. as per recipe.

14. Recipe cooking:  Close and look cooker cover. Automatic cooking program will start- 1. Steam valve will open. Temp. will increase from 55°c to 85°c. 2. Agitator will be switched to higher speed. After cooking temp. has been reached- 1. Steam valve will close. 2. Cooking temp. is maintained at a constant valve by temp. controller. 3. Cooking time commence. After cooking time is finished- 1. Agitator will be switched from higher to lower speed and continue to run at that speed. 2. Cooker cover can be unlocked and opened to check viscosity and concentration. For reservation of cooked size to storage tank- 1. Open manual valve of the corresponding tank. 2. Switched on size delivery pump with push button size is pumped in to the corresponding storage tank. 3. The size delivery pump is stopped automatically when the cooker is emptied or the maximum level in the storage tank is reached. 4. Switch on agitator of the corresponding tank with push button.   

15. Recipe cooking:  This cooked liquor is transferred in the size box of the main m/c called sizing center. A steam pressure of 3.5 bar (maximum) is required in the sizing center for the following types of steam heating.  Direct heating (controlled by pneumatic control valve) for the size feed box and the size box.  Indirect heating (controlled by automatic or manual operated valve) for vent in the size and size feed box (water bath). Temperature of water bath must be as close as possible to the boiling point of water.  The direct heating system should be switched on as less as possible by temp. control to maintain a constant temp. of about 80 to 85°c in order to avoiding diluting the size liquor where by preventing fluctuation in viscosity and hence varying degree of sizing.

16. The Important Features to be remembered During Sizing: The Important Features to be remembered During Sizing: 1. If the hairiness of the yarn is high then the concentration of the size would be high. 2. If the twist is high in the yarn then the concentration of the size would be high. 3. If the yarn (finer) count is high then the concentration of the size would be high. 4. If the yarn (coarser) count is high then the concentration of the size would be low. 5. If the temperature of the bath is high then the viscosity of the size would be less and vice versa. 6. If the cooking time is more than the viscosity would be less.

17. Effects of Sizing on Yarn: The amount of size add-on depends on yarn structure, sizing recipe, squeezing roller pressure, m/c speed. As the size add-on is increased—  The yarn becomes stiffer.  The yarn becomes less extensible.  The yarn becomes more difficult to weave. If a low add-on—  The yarn becomes hairy.  The yarn suffers from lack of strength.  The yarn becomes more difficult to weave.

18. GRAPH: GRAPH: If Sizing increase, Efficiency also increase up to optimum level. SIZE % Low Good Standard Optimum High Very high Extreme EFFICIENCY% 40 75 85 95 85 75 40

19. 95 100 85 85 90 75 75 80 70 efficiency% 60 50 40 40 40 30 20 10 0 low good standard optimum high very high extreme size%

20. If Sizing increase, End Breakage% also increase upto optimum level. SIZE % End Breakage% Low Good Standard Optimum High Very high Extreme 70 50 20 10 20 50 70 80 70 70 70 end breakage% 60 50 50 50 40 30 20 20 20 10 10 0 size%

21. Sizing Material & Chemical Used: Sizing Ingredients- 1. Starch. 2. Binder. 3. Softener. 4. Anti-septic agent. 5. Anti-static agent. 6. Weighting agent. Starch: Starch is the main sizing ingredients. They coat the warp yarn with a film & impart smoothness by binding the projecting fibres to the yarn surface. The viscosity of the size solution is controlled by the amount of starch, the recipe, degree of mechanical mixing, temperature & time of boiling.e.g. Potato, CMS(Carboxy Methylated Starch),PVA (Polyvinyl Alcohol) Binder: These materials penetrate into the yarn & contribute in increasing yarn strength. These materials can be used as an independent gum & substitute of starch products. e.g. Polyacrylamide, Polyacrylonetrile etc.

22. Sizing Material & Chemical Used: Softener: The hard fragile film is softened by addition of softener. They increase flexibility of yarn after sizing; e.g. Tallow, Soap, Japanese wax, Modified wax, Artificial wax. Anti-septic agent: The size recipe consist starch which the protein substances in the favorable medium for the development of the micro-organism (Fungi, Mouldetc). The sized warp or grey cloth is stored for long time; the anti-septic agent is used to prevent the growth of micro- organism in the grey cloth. Weighting agent: These agents are used to increase the weight of the fabric. The fabrics are to be sold at grey stage or require the special type of finishing to get fuller appearance are sized with the weighting agent.

23. THE FACTORS IN CHOOSING SIZE INGREDIENTS ARE- 1. The recipe should be that which gives fewer end breaks. 2. It should be that which gives the least exfoliation. 3. It should be that which permits easy de-sizing. 4. It should give good fabric characteristics. 5. It should be compatible with machinery (e.g. it should not cause size build-ups during weaving or blockages during slashing). 6. It should not cause any degradation of the textile material. 7. The cost of sizing plus the cost of weaving and finishing should be minimum.

24. Sizing Recipe: Sizing recipe depends on yarn type, total ends. Typical sizing recipe- In 500 Liter Water •Starch •Binder •Softener : 10-20%of water. : 2-4% : 0.5-1% of water. of water.

25. FACTORS AFFECTING THE SIZE TAKE UP PERCENTAGE-  Viscosity of the size recipe: If viscosity of the size liquor is not proper, it is difficult to penetrate for the size material to the core of the yarn.  Lubrication: Lubricant can exist at the surface or exist inside the structure and later work itself to the surface as the yarn rubs over a friction surface.  Degree of size penetration: It determines the stiffness for a given yarn bearing a given size. So if Degree of penetration is not proper, size take up% will be un- uniform.  Squeeze roller pressure: If the pressure of squeeze roller is not sufficient, size add-on may be increased or decreased.  M/C Speed: If m/c speed is high or low consequently size take-up% may be less or high correspondingly than the required take-up%.

26. Machine Setup: PARAMETER M/C RANGE SET VALUE 40-45 for Fine Cotton 45-50 for Yarn Dyed Material. 50-70 for Solid Dyed Material. Sized Speed 1-120 m/min

27. Machine Description: Machine Description: Slasher sizing machine is a continuous sizing machine. This machine has a number of units. For an ideal sizing machine following units are most common, 1. Back beam unit 2. Sizing unit 3. Drying unit 4. Cooling unit 5. Dividing unit 6. Measuring & marking unit 7. Beaming unit The machine in our lab is a semi automatic machine which is electrically driven by a heavy motor.

28. Yarn Path / material flow diagram

29. Key Accessories: 1. REFRACTOMETER. 2. VISCOSITY CUP.

30. Equipment: 1. BENINGER ZELL SIZING M/C (SINGLE SIZE BOX). 2. BEN SIZEMIX (COOKER). These sizing machines are equipped with BEN SIZEMIX size cooking & storage apparatus. A total of 12 (maxm) direct warped beams can be combined & sized to make weaver’s beam. Moreover an additional unwinding frame provides the facilities to size sectional warped beam.

31. MACHINE DESCRIPTION TOTAL SIZING M/C SECTION M/C NAME ORIGIN MODEL R.P.M. SIZE BOX BEAM CREEL VOLTAGE/FREQUENCY CONTROLED VILTAGE MAIN FUSE WORKING WIDTH SIZING BATH Rolls, : 01 : 01 : BENNINGER ZELL SIZING M/C. : GERMANY. : BEN PROCOMB ZB-20 SWATKECT 4/4/4. : 16-80 m/min. : 1. : 12. : 400V/50Hz : 20V/DC. : 20 A. : 2200 mm (between the flanges). : Working Width 2200mm, Roller Width 2400mm, 2 Dip 2 high pressure nip rolls with automatic regulation of the squeezing pressure, Size Bath in Stainless Steel, Automatic Size Supply Driven By Handy Mat, Pleva. DRYER : Cylinder dryer type ZT4/4 with 4 Teflon coated drums dia 800mm + 4 drums dia 800mm (possibility for adding 2 more drums), Steam Pressure 3.5-5 bar-147°C,automatic tension regulation by PC, Stainless Steel aspiration top with 2 ventilators. Automatic speed control MAHLO, dry separator, unroll device SWA.

32. M/C NAME ORIGIN CAPACITY STORAGE TANK PROCESS temperature & cooking time). : BEN-SIZEMIX. : GARMANY. : 600 Liter with Temperature regulation. : 1.45 Liter. : SEMI-AUTOMATIC driven by PCBEN-SIZEMIX (quantity of water,

34. Main parts Figure:

39. Main Parts: 7. Immersion roller 8. Sizing roller 9. Squeezing roller 10.Reverse box 11.Cooking box 12.Steam pipe 13.Drying cylinder 14.Guide roller 15.Moisture Roller 16.Tension roller 17.Lease rods 18.V- reed 19.Nipper roller 20.Warp beam 21.Pressure roller 1. Creel 2. Pre-Beam 3. Feeding r/r 4. Guide roller 5. Tensioner roller 6. Sizing box

40. Description: Back beam unit: In single end sizing yarns are taken from a creel rather than from a beam. This unit contains 12 carriers from where yarn is supplied. Indirect & direct process of yarn supply is frequently used for spun yarns. In case of indirect method beam creel is used. This beam creel can be arranged in various ways. Sizing unit: In this unit a size box is used to apply size to the yarn. The warp sheet is guided through the solution means of the immersion roller & then through the squeeze roller where the yarns are pressed to maintain the required size to up percentage by the yarn. The size box temperature is controlled by flowing steam through pipe. Drying unit: 14 heated cylinders consist of drying unit. This unit is required to dry the wet sized yarn rapidly, thoroughly & uniformly. A two cylinder dryer is too slow & it is difficult to maintain by it. But a multi-cylinder dryer is a good one to main in such a way that after drying. Yarn contains 6% water.

41. Description: Cooling unit: In this unit there is cooling fan & a guide roller. The cooling fan supplies cool air which extinguish the yarn temperature & also remove the moisture. Dividing unit: In order to prevent adhesion between the yarns, it is necessary to separate each sized end from the others. For this lease rod or breaker rods are used to divide the main warp sheet into single end. Measuring & marketing unit: This unit consists of colouring bowl which contains easily removable colour. This colour is used for making on sized yarn. Also there is a measuring roller which measures the length of sized warp yarn. Beaming unit: Finally the sized warp is wound on weavers beam.

42. Technological change due to sizing:  Increase in breaking strength: During sizing, adhesive material creates bonds between fibres to fibres which increase the strength of yarn. It increases 20-40% breaking strength of the fibre.  Increase abrasion resistance: After sizing the gap between fibres are filled with size and coating on the outer surface of the yarn take place.  Increase in stiffness: After sizing, flexibility or pliability of yarn is decrease and stiffness is increased.  Increase in elasticity: As extensibility of the sized yarn decrease, more force has to be applied to extent the yarn. Hence elasticity increases.

43. Technological change due to sizing:  Increase frictional resistance: Application of size materials makes outer surface of the yarn smooth and hence occurs less friction.  Increase yarn diameter: Sizing means coating adhesive on the outer surface of the yarn. Hence sizing causes increase of diameter of yarn.  Decrease in extension: After sizing the gap between the fibre does not occur easily. So the extension decreased.  Decrease in electrostatic charge: Electrostatic charge is formed due to the friction between yarns and roller. Size materials contain moisture which reduces static friction.  Decrease hairiness: During sizing protruding hairs of yarn fix with yarn end so yarn hairiness decreases.

44. Machine Start up: As the m/c is on enter all data/production parameter in the BEN PRECOMB unit at the head stock. Following data is entered- 1. Feed length and doff length. 2. Sizing degree i.e. pick-up%. 3. Tension and stretch over warp in different zone. 4. Drying cylinder temp. in different zone.

45. Faults of Sizing: 1. Sizing spots: Size material should be added gradually to the mixing tank for good mixing. If it is added at once, spots are appeared on the yarn. 2. Repeating warp streaks: This defect is due to uneven tension in the pre beam. 3. Shinnery: This defect due to the friction between the yarn and drying cylinder. 4. Sandy warp: Due to not crushed or grind the size material properly. 5. Ridge beam: This fault occurs due to uneven distribution of yarn in wraith.

46. Faults of Sizing: 6. Hard sizing: If the size materials are applied too much, the size becomes hard which cause hard sizing. 7. Improper drying: Under drying-Bacteria form-Yarn breakage-over drying-Hard sizing. 8. Size dropping: This defect due to not optimum the viscosity of the size solution. 9. Size stitching: Due to improper drying after sizing. 10. Uneven sizing: Due to over or under sizing. Due to over or under concentration of size liquor.

47. Calculation:

48. Required Chemical &no. of Mixing of Sizing Recipe: