Quality Assurance System in Dyeing and Finishing Section

In dyeing and finishing section, quality assurance system is used to measure the quality of dyed fabrics. Through checking the shade of dyed fabrics, the fastness properties can be worked out. Dyed fabrics will be issued with quality certificate, for them having good fastness properties.

The quality of dyed fabrics is assured in laboratory, dyeing section and finishing section.

In laboratory:
1. Receive swatch card from buyers according to their requirement.
2. Dye sample by manually or CCMS.
3. Dye sample until matching with swatch card.
4. Fastness & other tests of fabrics can be also carried out.

In dyeing section:
1. Dye sample in dyeing machine and dyeing shed, matching with the approved sample.
2. Move to bulk production, if the result is matched with approved sample.
3. During dyeing, take the samples when accurate shade matching accurate shade. The interval is lasted fro 30-40 minutes.
4. Collect dyeing sample which having been softened.
5. Last of all, collect sample from fixation & matched.
6. Allow fabrics to be finished.

In finishing:
1. Using a series of finishing machines maintains correct width, softness and appearance according to requirements.
2. Test samples for several times for GSM, shrinkage & fastness properties.
3. Inspect fabric and prepare for delivery.

Quality Assurance System Diagram for Textile Products

A quality assurance manager runs quality control department to ensure the quality of textile products during manufacturing. Quality of textile produces is checked in every step of manufacturing. For quality assurance system diagram, different international quality standards are adopted. Q.C department also helps CCMS test the quality of a textile material.

The followings are the quality assurance system diagram for textile products.
Yarn processing

Yarn test

Pass — Fail
↓ ↓
Knitting Send to spinning mill

Grey fabric inspection

Pass — Fail
↓ ↓
Grey store Send to store as reject

Batch making

Dyeing

Dewatering

Drying / stentering

Compacting

Fabric checking

Lab Inspection (Shade)

Pass — Fail
↓ ↓
Delivery Send to store as reject

Send to concern Department

Types of TTQC Lab for Quality Assurance of Textile Products

Textile Testing Quality Control (TTQC) lap is used to ensure the quality of textile products. TTQC lap plays a key role in the evaluation of textile products. Nowadays, producers are expected to supply qualitative product.

In textile industry, quality is assured at the every step of production. From the raw materials to the finished goods, quality control department assures the quality. Quality must be assured in fiber selection, yarn production, fabric manufacturing, wet processing and apparel manufacturing. The quality of dyestuff and chemicals which is used in dyeing, printing and finishing also should be checked. Mostly, quality control department gives a quality pass certificate so that finished products can be exported.

Educational institutes, research institutes for teaching the quality evaluation system and research have TTQC lab, so does as testing the quality of the textile products. Some TTQC labs are set up for commercial purpose. Some quality standardizing group also set up TTQC lab for testing the quality. TTQC lab also ensures the quality of the dyes and chemicals in dyestuff market.

Types of TTQC lab for quality assurance of textile products:

There are various types of TTQC:
1.Textile testing and quality control lab (TTQC Lab) in the Industry.
2.TTQC lab in the educational institute.
3.TTQC lab in the research institute.
4.Commercial TTQC lab.
5.Port TTQC lab.
6.TTQC lab in the standardizing house.
7.TTQC lab in the buying house.
8.TTQC lab in the dyestuff market.
9.TTQC lab in the arm force or defense department.

Stretch Cotton Weft Production Process Does Not Fall Down

Thermal underwear for winter can significantly “decompression”, the last two years the popular favorite fashion crowd. Vintage thermal underwear products, is added to the warm liner using thin layer of hot-melt film (commonly known as PVC plastic film) ways to enhance wind resistance, but easy to issue a “rustling” sound when wearing this product, and the impact of ventilation sex, there will be “feeling hot”, prone to static electricity. A new generation of thermal underwear products, including insulation layer between when microfiber woven from the system, so that both the soft and comfortable clothing and good thermal performance and light weight, good elasticity, moisture permeability, hand kneading, supple feel no foreign body sensation. The added Lycra underwear fabric, so that both vertical and horizontal elastic fabric, commonly known as lycra fabric, lining the core is made ​​of high elastic polymers.

1. fabric specifications
Stretch cotton weft not fall down 55% polyester / 40% cotton / 5% spandex, width 150 ~ 160 cm, mass per unit area of ​​280 ~ 300 g / m2 cotton weft lycra does not fall down from 24 to 28 anti pack towel machine needle weaving, using fine denier 150D / 288 FDTY raw material for polyester yarn terry, 14.8 tex / 40 D cotton spandex yarn package for surface silk, spandex content of more than 5%, excellent elasticity.

2. Process
Pre-shaped fabric ready → → → dyeing → ​​cutting ring plus soft bristles → dehydration → drying → ​​→ → carding fleece shearing → ​​→ complex setting.

3. production process

3.1 fabric ready
Prepare including the original cloth fabric inspection, turn cloth (in batches, boxes, print), sewing head mark.

(1) the original cloth inspection
Original cloth inspection includes physical indicators and appearance flaws, requires no oil jump yarn and yarn. General sampling volume of 7% to 9%.

(2) turn the cloth
When turning the cloth to note selvage neatly pull the cloth head can not leak, do the pros and cons, inside and outside the same. Because Lixin Dyeing Machine (ECO38, ECO6) each tube can accommodate up to 220 kg of fabric, so the required amount of points will be gray car, a car can be mounted two, each tube of cloth does not exceed 220 kg (8 bolts of cloth around).

(3) sewing head
Seam requires smooth, fastness, while Sarkozy, stitch density consistent, no leakage needle and needle jump. Note also that when the seam fabric specifications, positive and negative agreement. Two bits of cloth sewn head interface should be encrypted, encryption length is 1 ~ 2 cm, to prevent the occurrence of dyeing cloth off processing. When connected to a cylinder knitted fabric will draw attention to two of cloth needle-bit aligned before connecting.

3.2 presetting
The purpose is to eliminate the existing pre-shaped crease on the fabric, increase fabric dimensional stability and morphological stability, to ensure that is not easy to produce difficult to eliminate wrinkles subsequent processing and administration, and terry upright. Process overfeed needle into the fabric → clip chain (overfeed 6% ~ 7%) → hot air drying room (165 ℃, 50 s) → cooling drop cloth.

3.3 shear ring
Circle of cloth cut speed 30 ~ 40 m / min, the spiral blade speed 5000 ~ 6 000 m / min, the tension is moderate.

Note:
(1) in the regulation of shearing gauge, should gradually from large to small, while adjusting the side effects observed in order to achieve the best position.

(2) sewing head to dense, homogeneous, prison, to minimize I sew, otherwise there will be torn, wrinkled, or even form a shearing uneven or rag.

(3) After the fabric, the fabric is not deviation, can not have wrinkles or curled, so as not to cut circles uneven or broken scissors.

(4) Note that the right amount of fuel to the spiral cutter, too much fuel will spill soiled fabrics; too small, spiral knife blade will overheat and shut down.

(5) joints through notches, to promptly carry a knife, lift and fall to firmly but gently, not tainted scissors.

Before (6) into the machine to pay attention to the positive and negative fabric, the fabric should be against the shearing direction into the cloth, so terry fully upright.

(7) fabric tension should be moderate, longitudinal tension is too large terry lodging easy to make it difficult to cut; tension is too small, loose fabric on both sides, prone to broken edges.

3.4 Staining

3.4.1 dyed polyester
High temperature high pressure dyeing machine dyeing polyester.

Dyeing prescription:
Disperse Orange S-ER /% (omf) 0.475
Scattered ruby S-2GFL /% (omf) 0.19
Scattered blue S-2GL /% (omf) 0.31
Glacial acetic acid / (g · L-1) 0.7
Leveler GS / (g · L-1) 0.5
Dispersant / (g · L-1) 0.5
Degreaser / (g · L-1) 0.5
Bath ratio of 1:15
Reduction cleaning prescription / (g · L-1):
Reducing cleaning agent HY01 1
Glacial acetic acid 0.5
Bath ratio of 1:10
Technology curve (slightly)

3.4.2 dyed cotton core-spun yarn
Process: chemical materials → dyeing → ​​fixing → ​​washing → soaping → ​​washing → ​​drying.
Technology prescription:
Reactive Red /% (omf) 0.12
Reactive Yellow /% (omf) 0.08
Sodium Sulfate / (g · L-1) 30
Soda / (g · L-1) 20
Dispersant / (g · L-1) 0.08
Soap lotion / (g · L-1) 0.6
Bath ratio / (g · L-1) 1: 50
Technology curve (slightly)

3.5 plus Sophie
The purpose is to add soft fabric having a soft, smooth effect, can also improve the elasticity of the fabric, and the antistatic properties and the like.

Technology prescription:
Softener (Changzhou tomorrow) / (g · L-1) 0.5
Antistatic agents (Changzhou tomorrow) / (g · L-1) 0.5
Smoothing agent / (g · L-1) 0.3
Temperature at room temperature
Time / min 10
Bath ratio of 1:20

3.6 dehydration
The fabric was uniformly stacked in the rope is mounted on a vertical shaft of a centrifugal dewatering machine perforated cage, the cage speed operation, the moisture in the fabric due to the removal of the centrifugal force. After the cotton fabric components centrifugal dewatering machine dewatering, water rates in the 30% to 40%, does not make the deformation fabric structure.

3.7 heatset
Covering for surface silk cotton ammonia organization DTY organization for cotton weft pile velvet fabric lycra does not fall in a series of dyeing process, due to repeated mechanical action and repeatedly stretching, the original fabric width and coil geometry produces deformation and contraction, or even skew, through the heat setting to improve the dimensional stability of the fabric, enhanced anti-wrinkle properties. Spandex is not due to high temperature, therefore the heat setting temperature is not too high, try not to exceed 160 ℃.

Conditions:
Equipment cloth clip Stenter Machine
Temperature / ℃ 150 ~ 160
Speed ​​/ (m · min-1) 45
Overfeed /% 10
Under the machine width is 160 ~ 165 cm, mass per unit area of 280 ~ 290 g / m2.

3.8 bristles
Using B light machine needle bristles bristles, speed 15m / min.

Note:
(1) contains a certain amount of moisture to the fabric in order to increase the friction between the fabric and the needle, is easy to bristles. General moisture content of 15% to 10% is more appropriate.

(2) before the bristles should check whether there are remnant fabric edges, holes, and drag yarn for wear part, should advance repaired or removed.

(3) To smooth fabric joints, the back to take together, with dual-channel solid seam, seam less, do not generate the wrinkles.

(4) the effect of fabric tension directly affect the bristles. Tension is too loose, weft yarn moves away, tissue deformation, resulting in uneven bristles. If the warp tension is uneven, such as an intermediate or intermediate loose tight loose sides tight sides, the bristles also generate unevenness, can increase the tension of the tension roller properly, so that the entire fabric formation, even bristles.

(5) the depth of the bristles order to try to separate from dark to light. Because dark colored stains on the obvious fluff, and vice versa, it is very obvious.

(6) cloth of varying size specifications joints should not exceed 2 files, in order to avoid collapse occurred.

3.9 carding
Carding purpose is to erect pile fabric has bristles to evenly shearing.

Conditions:
Large cylinder / (m · min-1) 70
Cloth speed / (m · min-1) 23
Tension 1 / ° 50
Tension 2 / ° 50
Tension 3 / ° 50
Left Brush / times 12
Right Brush / times 12

3.10 Shearing
Process flat pieces of cloth into pieces → → extended tension mechanism → shearing roll → drop cloth.

Conditions:
Speed ​​/ (m · min-1) 15
Wind /% 100
Spiral blade speed / (r · min-1) 1500
Clearance / mm 2
Tension / ° 50
Shearing number one

3.11 fleece
Fleece processes play a decisive impact on the product’s style. Usually the first pass into the 80 ~ 100 ℃ steam so wispy hair form, after repeated rolling fleece, with a hot wind to 90% dry, sub-blowing cold air, so that the fabric can appear the same size and hair neat and tidy tufts.

Process conditions: temperature / ℃ 100, time / min30

Note:
(1) the amount of steam for the formation of hair bundles have a significant impact, a small amount of steam, hair loose and difficult to form tufts.

(2) Length drying time also affects the size of tufts and loose, more dry cloth, velvet bundle more upright, more three-dimensional sense.

(3) The entire fleece during good or bad times in order to ensure that the big drum roll, otherwise it will cause uneven size tufts or end bad.

(4) After cooling to promptly remove the cloth from the big drum, and it spread out in time to avoid the formation of wrinkles.

3.12 Complex setting
Because the fabric stained rope way, and after the brush, mechanical action comb, scissors, rock and other processes, the fabric will shrink vertical and horizontal stretch, causing uneven width and latitudinal lines skew phenomenon, it should be complex setting.

Process conditions: temperature / ℃ 150 ~ 160, speed / (m · min-1) 45, overfeed /% 10, the next full-size machine width is 160 cm, mass per unit area of ​​300 g / m2.

Defects and Wastage in Winding

In winding, transformation spinning bobbin yarn to yarn package is carried out manually. For that, some defects may occur in winding. During types of defects can be found. The following are the main defects in winding.

Defects in winding:
1.Patches are formed on the yarn.
2.Incorrect winding speed.
3.Yarn tension varying.
4.Packages are dirty.
5.Yarn package has incorrect shape.
6.The yarn has too much knots.
7.Excessive full bobbin.
8.Piecing up.
9.Over lapping.
10.Two end winding.
11.Mixing yarns with different density of linear.
12.Greasy and dirty yarn.
13.Poor yarn cleaning and snarling.

During process, defects in winding should be concerned about.

Wastage in winding: In winding section, different reasons can cause wastage. The followings are the main reasons:
1.Knots on package
2.Ends are still remained after tying.
3.Yarn slough off.
4.Coil is remained on the yarn package.
5.Short ends dropped at threading.
6.Greasy and dirty yarn.
7.Workers negligence.

The sizes of the spinning bobbin and breakage rate have great influence on the quantity of wastage. Increasing the package size and reducing the breakage rate of yarn, wastage in winding is fallen.