Hydro Extractor Machine for Dyeing Knitted Fabrics

Hydro extractor machine is the first sequence of dyeing knitted fabrics. After dyeing being completed, knitted fabrics are hold for a while before hydro extraction. Hydro extractor machine is vital for de-watering process.

Functions of hydro extractor machine: Hydro extractor machine uses centrifugal extraction to remove excess water from knitted fabrics. About 65% water is removed by hydro extractor machine which spends 5-10 minutes.

Procedure of hydro extractor machine: Hydro extractor machine looks like a round basket which is made of steel. It has amount of holes on the down side of basket. Put the wet knitted fabrics into the hydro extractor, then water is removed by centrifugal extraction. Extract water is drained out through the holes.

Nowadays, various types of hydro extractor machine are available in the market. People can choose what they need according to their own requirements.

Types of Knitting Machines in Textile Industry

Knitting machines are used to produce knitted fabrics by using hooked needle to interlock one or more yarns through a series of loops. Knitted fabrics differ from other fabrics according to the design. Specific knitted fabrics are produced by specific knitting machine.

Knitting machines are classified into the following types:

Weft Knitting Machine
>Flat Bar Knitting Machine
1. Flat bed
2. V-bed
3. Single bed
4. Unidirectional

>Straight Bar Knitting Machine
1. Single needle
2. Double needle

>Circular Knitting Machine
1. Revolving Cylinder; Sinker Top or Open Top Single Jersey Knitting Machine
2. Revolving Cylinder; Cylinder and Dial Double Jersey Knitting Machine

>Circular Bearded Single
1. Sinker Wheel Knitting Machine
2. Loop Wheel Knitting Machine

>Warp Knitting Machine
1. Rachel Knitting Machine
2. Tricot Knitting Machine

Nowadays, knitted fabrics have a large verity to meet the different demands. Such types of fabrics are produced in the knitting mills.

Process of Manufacturing Knitted Fabrics

Knitting is the interlocking of one or more yarns through a series of loops which is the main activities for producing knitted fabrics. In every mill, a sequence is maintained in production processing. In every step, person should be responsible for the best production. The followings are the process of manufacturing knitted fabrics.

Firstly, a production is supplied to knitting manager from the merchandiser, according to the requirements of consumers. Then he informs or orders production officer about it and provides the schedule for producing targeted production.

1. Getting the analysis from knitting manager, design and draw a cam setting for producing the desired fabrics.

2. Getting the information, production officer informs technical who is in charge and knows about machine which the production will be run.

3. Technical in charge calls for leader of mechanical fitter troops who also take decision about machine for production considering machine condition, machine types, production capacity and maintenance complexity.

4. Production officer adjust required stitch length and grey G.S.M for getting final G.S.M., cooperating with experienced mechanical fitter.

5. Supervisor checks production regularly and makes operator consciously about finishing tin due time who is also maintain daily production report sheet and responsible to inform the production of that day to knitting manager.

6. Operator runs machine in high attention in case of faults in the fabrics. Any faults are found, he will call for the mechanical fitter who is in duty. Then, mechanical fitter fixes it or informs it the technical in charge. The technical will take necessary to remove the problem.

7. During production time, quality department also checks the fabric. If any faults are found, they will inform it to the technical in charge. Technical also takes necessary steps for reducing the faults in knitted fabrics.

8. When knitted fabrics completed, knitted fabrics will be sent for quality check. If the fabrics pass the quality, they will be sent for the next process.

Definition and Types of Knitted Fabrics

Fabrics are produced from a set of warp or weft yarn. Weaving and knitting differ for interlacing techniques of yarn. In weaving, warp and weft yarn are used for producing woven fabric. For knitting, a series of yarn in warp or weft directions are made of fabrics.

Knitting is defined as the process that sets connect loops from a series of yarn in warp or weft direction to produce fabrics. Various knitting machines are used to perform knitting. In general, knitted fabrics are classified into warp knitted fabrics and weft knitted fabrics.

Warp knitted fabrics: In warp knitted structure, different thread and the number of thread is made of each loop in the horizontal direction. Fabric is at least equal to the numbers of loops in horizontal row.

Weft knitted fabrics: Use one thread runs in horizontal direction to make a horizontal row of loops. The structure of weft knitted fabrics is different from that of warp knitted fabrics. Weft knitted fabrics have worldwide popularity.

In daily life, different knitted fabrics are used. Depending on the design of fabrics, knitted fabrics are classified into following types.

>Single Jersey
1. Plain Single Jersey
2. Single Jersey with Lycra
3. Single Lacoste
4. Double Lacoste
5. Single Pique
6. Double Pique
7. Polo Pique
8. French Terry
9. Terry with Lycra
10. Fleece
11. Fleece with Lycra

>Double Jersey
>Rib Fabric
1. 1×1 Rib
2. 2×1 Rib
3. 2×2 Rib
4. Lycra Rib
5. Flat Back Rib

>Interlock Fabric
1. Plain Interlock
2. Drop Needle Interlock
3. Interlock with Lycra

>Collar and Cuff
1. Plain Collar or Solid Collar
2. Shaving Collar
3. Jacquard Collar
4. Tipping Collar
5. Race Collar
6. Stripe Collar

Knitting machines also develop various types of decorative design. In modern times, auto stripe knitting machine is used to produce multi color stripe fabrics, which cannot be produced by normal knitting machine.

Knitted fabrics have different properties. Knitted fabrics depend on the atmospheric condition of the country.

Parts and Functions of Knitting Machine

Knitting machine can be classified into circular knitting machine and flat bed knitting machine. Both of them are widely used. A knitting machine consists of lots of parts. Every part is vital for running machine smoothly and has its own function.

Different parts of knitting machine and their functions:

>Creel: Creel is also called as the holder of cone. Cone is placed in a creel for feeding the yarn to the feeder.
>Feeder: Yarn is feed through the feeder which depends on the design of fabric.
>VDQ pulley. VDQ pulley is used for controlling the stitch of the fabric.
>Guide: Guide also called as the supporting element which is used to guide the yarn.
>Sensor: Sensor is an automatic controlling system which yarn passes through. If any yarn breaks down or problems occur, sensor system will stop the machine automatically.
>Fixation Feeder: Fixation feeder is used in electrical auto striper knitting machine to feed the yarn at specific finer.
> Rethom: Rethom is used in electrical auto stripper knitting machine.

Faults of Knitted Fabric in Production

Loop formation produces knitted fabric which should be careful. Various types of faults can be found in knitted fabric, which caused by fabric rejection. Find out defects of fabric during production. Then, steps can be taken to remove them from the next knitting production process.

In practical: The followings are the faults which could be found on the knitted fabric.

Hole Mark
>The yarn breaks in the rejoin of the needle hook during loop formation.
>Caused by yarn breakage or cracks.
>The yarn is not correct on regarding structure, gauge, course and density.
>Badly knots or splicing.
>Badly set of yarn feeder.

Needle Mark
>Needle marks come along the fabrics when a needle breaks down.
>If a needle or needle hook is slightly bends, then needle mark comes on the fabrics.

>Buckling of the needle latch.
>Yarn tension variation during production.
>Low G.S.M fabric production.

Sinker Mark
>Sinker may corrode for abrasion. So it cannot a new loop and result in sinker mark coming.
>Sinker head bends. Then sinker mark comes.

Drop Stitches
>Yarn is not feed properly during loop formation.
>Using defective needle.
>Take down mechanism is too loose.
>Insufficient yarn.
>Set yarn feeder badly.

Oil Stain
>When oil lick through the needle trick then it pass on the fabrics and make a line.

Rush Stain
>Rush in the machine.

Pin Hole
>Break down or bend of the larch causes pin hole on the fabric.

Grease Stain
>Improper greasing in the machine.
>Excess IF greasing

> when an empty needle with an empty needle with close latch runs into the yarn feeder and remove the yarn out of the hook of the following needles, then cloth fall out occur after a drop stitch.

>Yarn fault
>Different micro near value of fiber content in yarn.
>Different luster and dye affinity of fiber content in yarn.
>During spinning different similar classes of fiber is mixed specially in carded yarn and these fibers have similar characteristics.
>In draw frame different similar classes sliver is mixed and make one sliver.

Yarn Contamination
>Yarn contains foreign fiber. And the foreign are remained in the fabric even after finishing.
>Lot mixing and count mixing.

Fly Dust
>In knitting section too much lint or short fiber is flying to and fro that are created from yarn due to low twist as well as yarn friction. This lint may adhere or attached to the fabric surface tightly during knit fabric manufacturing.

Yarn Faults
>Different yarn faults
>Yarn count variation
>Thick/Thin place in yarn

Knitted machine should have perfect conditions. Faults are not allowed to exist in needle, sinker, feeder and other equipments.

Computer jacquard knitting machine to produce the wrong flowers, what is the reason squandering?

If you do not consider the special circumstances of particular organizations brought only consider the needle incorrect due to wrong flowers and squandering the case, there are the following possibilities:

a. poor knitting machine needle selection with the degree of synchronization itself, will lead to irregular squandering the entire disk, then re-adjust the parameters to the machine.

b. jacquard depth selector plate is not pressed, it will result in a lateral squandering. Jacquard middle pin is pressed into tablets linked, if the middle pin is depressed is not enough, the final intermediate needle still be quite straighten triangle knitting needle, appears certain large ones flowers confusion, squandering transversely.

c. Jacquard abnormal wear piece (jack or pins are similar phenomenon), will cause vertical squandering.

d. loom assembly design problems, resulting in an overall pattern confusion, this problem is relatively rare.

e. reset triangle or jack three track design or processing problems, resulting in particular large ones squandering. Problems in the case of being worn or fitted rear triangle design appears.

f. (position selector will jacquard sheet when pressed into the deepest barrel) relative to the needle selection jack triangle, the two are too close, leading to squandering. Middle pin needle selection is not completed action (being pushed jacquard pieces linked) has entered jack triangle track, leading to squandering, usually lateral squandering the entire disk.

g. selector and jacquard pieces assembled position with the heel of the poor, leading to squandering. For example selector at the head of this should not be pressed to lift jacquard piece, but because the low mounting position selector leads down to the jacquard piece, which appeared certain large ones squandering.

Investments on Tunisia Apparel and Textile Industry Declined

Recently, Tunisia Industry Promotion Agency stated that their Industrial investment in the first seven months of 2014 reached 1.83 billion TD. It decreased by 19.1% when compared with 2.26 billion TD in the same period of 2013(1 TD is equivalent to about 0.57 USD ). Among that, the investment on textile and garments industry declined by 4.5% on year-on-year basis.

The department stated that there are totally 32,439 job opportunities produced by Tunisia industrial investment in this year. However, this is less than that of last year, which created 38,500 job opportunities.

Since the beginning of 2014, chemical industry has an investment growth of 10.6%. Except that, investments on other main industrial fields have all decreased. Investment on shoes and leather industry has declined by 10%. The machinery industrial investment has declined by 7.4%. While that of apparel and textile industry has decreased by 4.5%.

In addition, the foreign investments of joint ventures in Tunisia have decreased also from 1.1 billion TD in 2013 to 0.64 TD, with a huge gap of 41.9%. However, investments of exclusively foreign-owned enterprises have increased.

More and more foreign investors become unwilling to cooperate with local merchants. This phenomenon is thought provoking.

Pigment Printing on Cotton Fabric

Pigment is a kind of synthetic organic materials. Pigment printing applies pigment paste on the surface of cotton fabrics so that can produce attractive design. Pigments are found in particle state and the particle size range should be in the region of 0.1 – 3 microns.

Pigment printing should be used with binder system together. As is known to all, pigment has no affinity on cotton fabric. For this, binder system is necessary during printing. The binder is a film that forms substance to make up of long macromolecules when applied to the textile materials to produce a 3-dimensional networked. The 3-dimensional links are formed during some suitable fixing process, consisting of dry heat and changing in pH value (<5), bringing about self-cross linking or reaction with suitable cross-linking agent. This cross-linking improves the elasticity and adhesion of the film to the substrate.

Advantages of pigment printing:
1. Both natural and synthetic fibers can use printing pigment.
2. Pigment printing is easy for using.
3. Pigment printing has the highest economical efficiency.
4. Pigment printing allows maximum output of goods.
5. Pigment printing has good fastness.
6. Pigment printing has good defined design.

Disadvantages of pigment printing:
1. Pigment printed textile has less comfort.
2. Pigments are sensitive to crushing during roller printing.
3. Rubbing fastness is medium.
4. Pigments are completely fast to dry cleaning.

Process of Printing Synthetic Fabric

Compared with natural fabric, the process of printing synthetic fabric is easier. It is know that printing process depends on the characteristics of fiber. In cotton printing, the fabric needs to be pre-treated before printing while the pre-treatment of the fabric is not essential for synthetic fabric, because synthetic fabric does not contain impurities like natural fiber.

Process of printing synthetic fiber: Synthetic fiber has various types, and the printing process for synthetic fiber is not the same. The process of printing nylon varies from the process of printing polyester. And it also depends on the dyes and pigments.

The followings are the common process for printing synthetic fabric.

Fabric from weaving section



Jet Dyeing







Folding or Rolling


Polymerizing different monomer can produce synthetic fibers. After printing, finishing is done for adding some properties. So the printing sequence should be aware of.