Yarn to Fabric Manufacturing
A case study on spun yarn production to fabrics and finishing processes in a real-time production environment
- 1 FINISHING
- 1.1 Machines used in Finishing
- 1.2 SINGEING
- 1.3 SPECIFICATIONS
- 1.4 WET SECTION
- 1.5 OPEN WIDTH WASHING
- 1.6 SCOURING
- 1.7 HEMMER MACHINE
- 1.8 MAT MACHINE
- 1.9 DOLLY MACHINE
- 1.10 HYDRO-EXTRACTOR
- 1.11 MILLING
- 1.12 SHEARING MACHINE
- 1.13 KIER DECADISER PROCESS
- 1.14 SUPER FINISH
- 1.15 FORMULA No. 1 PRESS MACHINE
- 1.16 PERCHING MACHINE
After mending the fabric comes to the finishing department where fabric is treated. Textile finishing is the term for chemical and mechanical processes used on fabric to achieve desired effects and it can have aesthetic or functional benefits. Finishing processes might modify a fabric’s final appearance, make it softer, or improve elements of its performance.
In OCM, the finishing department was divided into two sections
- Wet finishing
- Dry finishing
Machines used in Finishing
Singeing is a process applied to both yarns and fabrics to produce an even surface by burning off projecting fibers, yarn ends, and fuzz. This is accomplished by passing the fiber or yarn over a gas flame at a speed sufficient to burn away the protruding material without scorching or burning the yarn or fabric.
The singeing machine consists of three sections:
- Brush section – For cleaning of the dust
- Burner – It is attached with LPG for the removal of extra fluff
- Water rollers – It is used to cool down the warm fabric
- The singeing machine: Osthoff-senge VPGG
- Model: U9793 and total machines are 1
- Speed of the machine:90-120 RPM
- The intensity of the flame is 12 millibar (all wool)
- The intensity of flame for terry wool is 8 millibar
- The intensity of flame height: 6mm & temperature of flame camber -110℃.
Here the fabric is washed using detergent. This is done to remove the dirt and oil stains from the fabric
Two types of washing-
This is a process in which fabric is washed in rope form. Only crease-resistant fabric is washed by this process because the fabric is twisted while washing.
- All wool and terry wool fabric is
- Time took – 20 mins to 30mins
- Total no. of machines –12
- Speed of the machine – 50 to 60RPM
- For coarser fabric, soda ash is
- Maximum temperature -55℃
- Softener is used for harsh fabric
OPEN WIDTH WASHING
This is a process in which fabric is washed in open-width form. Hence, the anti-crease-resistant fabric can be washed.
- Fabric blends like poly viscose, poly-wool silk is
- Total no. of machines –1
- Ithas6tubs(1-soaping,4-water washing,1-acetic acid bath to neutralize the fabric)
- Temperature -45℃
- Speed of machine – 12-15RPM
- Highest speed – 20RPM
- Scouring is a process in which we remove the natural impurities, dirt, greasy spots (from loom), etc.
- These impurities interfere with the subsequent finishing process, therefore scouring is a must.
- Therefore a special scouring process is carried out in which the material is first padded with special scouring chemicals on jigger and the batch is left overnight.
- After this process, normal scouring is carried out on the dolly rotary machine.
- The composition of scouring liquor is governed by the nature of oil which has to be removed. Scouring chemicals are generally acetic acid and soda ash.
- This machine is used for both scouring and milling the fabric.
- Both length milling and width milling can be done in this machine.
- It consists of two pairs of top rollers and bottom rollers.
- Fabric is passed between these rollers in rope form.
- Plates are provided which can be controlled pneumatically.
- The water inlet and drain valve are also open closed pneumatically. Machine capacity is 200 kg.
- It is also used for both scouring and milling (length and width milling).
- It is also a rope scouring machine and consists of two pairs of rollers and four metallic plates(backside) this machine contains four drain valves and four inlet valves.
- A pump is provided in the machine, which brings the chemicals from the stock tank to the main vessel.
This machine is used for scouring and width setting of the fabric.
- The dolly machine is constructed with two heavy squeeze rollers and guide rollers. The bottom-heavy roller is driven by chain pulley drive given from outside.
- The top roller rests on this roller with fabric between them in rope and is frictionally driven.
- A metallic plate is situated under the heavy rollers to catch the expressed liquor. The pieces of cloth are made into endless chains in such a way that they pass through the squeeze rollers, over guide rollers, and under them though.
- The top roller is soft rubber coated and the bottom roller is made of hard ebonite.
- In the metallic plate, a steam pipe is provided which is perforated to heat the water. Four jets of water at the backside of the machine spray water with force onto the fabric.
- Max nos of four ropes can be treated together and the maximum capacity of dolly machine is 150kg.
- After washing, the hydro extractor is used to remove extra water from the fabric.
- Production – 9800mt/shift depends on the weight of the fabric.
- 30 minutes is required for 300-350m of fabric.
- This process follows the principle of centripetal force.
It is done to shrink the material to the maximum possible extent so that it does not shrink during its end-use. This process is based on the principle that the wool gets shrunk when it is rubbed in wet conditions and at a certain temperature.
- The lot is loaded into the machine and its ends are stitched together to form an endless rope.
- The machine consists of a fan, which blows air onto the fabric so that it opens before entering the compressing zone with closely placed steel bars followed by squeeze rollers.
- The fabric then slides over the tray in the plaited form before being drawn away by the winch rear and thrown into the milling liquor. During the milling cycle, the milling liquor is also continuously sprayed over the material before entering the compressing zone.
- The liquor is withdrawn from the additional tank, which is continuously replenished by withdrawing the milling liquor from the bottom of the machine.
DRYING AND HEAT SETTING
- The drying and heat setting both are done by a stenter.
- The essential part of the machine, the endless chain called pin plates runs forward each side of the stenter frame.
- The fabric lies stretched in open width across the center frame and between the two chains of the pin plates.
- It then rises upward in front of the operator and is contacted by the first scroll roller, then by a smooth idling roller followed by the main feed roller, rubber-coated to ensure good control.
- As the chains move forward carrying the fabric, it is arranged that they gradually diverge to the required width and the fabric is thus stretched out to the width.
- Once the fabric has been brought to the required width, the two chains of the pin plates run parallel and take the fabric through a long, lightly constructed, heat-insulated chamber where the drying takes place
- It reaches a point when it leaves the pin plates and is folded into laps in the trolley.
- Near the end of the machine, the fabric is lifted off the pins by the driven take-off roller and passes around a pair of draw rollers, which deliver to an overhead plaiting mechanism.
- A large wire mesh screen is fitted in the side to remove fly or lint entering the system.
- Heat setting is done to avoid the formation of creases and shrinkage
- A drying machine is used for drying the fabric.
- Machine used – Harish Hot Air Stenter (supra 5)
- Speed is about 15-20 RPM.
- For terry wool, the speed is 20 RPM
- To clear out the random length fibers and produce a uniform and level pile.
- To reduce the height of the wild fibers and prevent pilling.
- To produce a certain handle.
- To improve the colors and appearance of the fiber.
- In a shearing machine, there is a spirally wound shearing blade, which revolves in contact with a ledger blade.
- The fabric passes over a cloth rest in front of the ledger blade and the raised fibers flop against the ledger blade and are cut by the rotary blade.
- Suction units are incorporated for cleaning the working units .an automatic seam unit allows the steam to pass through.
- There are six searing units divided into three sets, each seat working on both faces of the fabric simultaneously.
- In this machine, the speed of the fabric passage through the machine is 20-25 meters/min and the speed of the spiral blades is 1200 rpm.
DECADAZING PAPER PRESS MACHINE
- It is done to give silk shine effect or in other words, it is a sort of shine treatment to the occasional wear fabric.
- The paper press machine consists of electronic cardboard which has a heating element in
- Fabric is sandwiched between these electronic cardboards and heated for an hour then 2 tons of pressure is created using hydraulic power and is applied for 8hours.
- Production – 1100 m in 14hours
- Used for costly wool.
- The material after cropping which is not decreased is taken for rotary pressing.
- It is a continuous process i.e. fabric is fed from one side and is pressed in the machine with the help of an iron roller and pressed fabric received from another side of the machine.
- The machine consists of a roller and a metallic plate having the same curvature as that of the roller.
- The material entered is taken over the vertical moving roller, which is hydraulically controlled to properly align fabric at the center of the machine.
- The material is passed over two brushes to remove dust and loose fibers. The material is then taken to the main pressing zones.
- Under this roller is a heated steel plate that can be moved up or down to press the fabric against the roller. The rotary process gives the fabric a crisp handle and increases in luster.
KIER DECADISER PROCESS
- This machine is used to give smoothness, luster, and soft surface to the fabric.
- Also, it provides bulkiness to the fabric and also controls fabric shrinkage both lengthwise and widthwise.
- It is also called final finish as after this, the finished fabric will not shrink after washing, generally in the case of wool fabric, as during spinning and weaving, the fibers get stressed( due to sulfide bonds in wool structure).
- In kier decreasing, the sulfide bonds get relaxed and get rearranged.
- Wool is set at the temperature of 200℃ and pressure2.5kg/sq.cm.
- This machine consists of a large diameter rotating cylinder.
- It is heated internally by steam. An endless thick belt (silicon rubber blanket) is arranged which presses lightly against the greater part of the cylinder to ensure that there is no friction or slip between the two.
- The suitably damped fabric is fed between the blanket and cylinder and is so laid around the cylinder until it arrives at a point where the blanket leaves the cylinder and under the influence of this pressure and the moisture from the steam, the fabric has its surface completely smooth to acquire soft handle.
- The temperature of the roller is kept at 140 degrees. This machine gives a smooth handle and lustrous look to the fabric.
FORMULA No. 1 PRESS MACHINE
- With silicone belt.
- Double time press machine.
- The temperature and pressure for this process are at 135℃ and 90kg/sq.cm.
- Total machines – 2
After finishing, the fabric is inspected in the perching machines where slubs, knots, holes, and other such defects are inspected.