1. Basic knowledge of dye vats
1. The machine basically consists of a cloth storage tank, a circulation system, a filter and a heat exchanger, a feeding barrel (auxiliary tank), a cloth discharge roller and a shaker. It is composed of folding device and control system.
2. The circulation of dye liquor is realized through a circulation pump driven directly by a motor. The circulation pump sucks the dye liquor from the bottom of the machine and sends it to the nozzle through the heat exchanger. The nozzle pressure is adjusted by the throttle valve installed on the outlet of the circulation pump. When the main pump motor is driven by a frequency converter, there is no throttle valve. .
3. The pressure gauge and temperature gauge are installed on the machine to display the nozzle pressure and dye liquor temperature respectively.
4. The front part of the heat exchanger is a filter, and a filter screen is installed inside it to cut off the lint in the circulating liquid flow. The heat exchanger is equipped with a heating/ Cooling valves are used to heat/cool the dye liquor respectively.
5. The rope-like fabric runs to the front in the cloth storage trough and is lifted by the lifting roller driven by the frequency conversion speed motor. Its speed is displayed on the electric control box. on the speed display.
6. The feeding barrel (auxiliary tank) is used for the preparation of dyes and chemicals. Open the water inlet valve or the return valve, and put clean water or dye liquor into the feeding barrel. The solution can be stirred by an electric stirrer, and the liquid can be heated by opening the direct steam heating valve.
7. Warning: When the temperature of the dye liquor exceeds 85℃ [185℉], the return valve is not allowed to be opened.
2. Preparation specifications before dyeing and dropping into the vat
1. When the previous vat of cloth is being dyed and kept warm, find the next round of cloth and push it to the front of the dyeing machine for storage. If the next round of cloth is not ready, notify the cloth preparation team to complete it as soon as possible.
2. Before each vat is clothed, the relevant information must be checked according to the requirements on the work order, such as the odd number of cloth types, the number of cloths, whether the cloth is evenly prepared, etc.
3. Pay attention to whether the last vat of cloth has been made into dark cloth. If you have made dark cloth and then dyed light-colored cloth, you should ask the color matching table to prescribe a prescription for washing the vat. [The recipe for cleaning the tank usually uses multi-foaming additives: NaOH, Na2S2O4, 95℃×20′ washing water for one tank]
4. Especially check the cloth used to pump the cylinder. Have you fanned the cloth well? If the cloth in the air cylinder is not fanned properly, the cloth will be twisted when cooking or dyeing. Cut three-inch holes in plain fabrics and garment fabrics to allow ventilation. Cut four-inch holes in double-sided and ribbed fabrics. hole.
5. After preparing the cloth for dropping into the vat, send it to the additive room to weigh out the required additives. Each additive must be checked and correct before it can be dropped into the vat.
6. The cloth used in the cylinder, whether new or reworked, must be checked and weighed to prevent leakage.
3. Specifications for cooking cloth in a vat
1. First of all, understand Knowledge of cloth boiling (refining), cloth boiling will use chemical methods to remove pigments and impurities on the fibers, and improve the water absorption and whiteness of knitted fabrics, especially the whiteness of two-color combinations.
2. Cloth cooking aids generally include HA alkali oil, GLM anti-wrinkle agent, 4+8 degreaser, NaOH burning salt, H2O2? hydrogen peroxide, HAC acetic acid, ENIYME degreaser oxygen enzyme.
3. First fill the empty tank with water, about 1/3 or 2/3 of the water level, first drop HA, GLM, 4+8, raise the temperature to 50°C, and then fill the whole tank with cloth.
4. After entering the fabric, adjust the water level, machine speed, and the time required for setting.
5. Add NaOH about 5′ after entering the cloth row. After adding NaOH, the auxiliary tank should be cleaned with clean water and then use return water to add H2O2. If the auxiliary tank is not cleaned at the end, there is NaOH. Residual, when H2O2 comes into contact, a chemical reaction will occur, and a lot of foam will appear in the secondary cylinder.
6. After filling in the cloth and adding additives, select the holding time according to the computer program.
7. When the air cylinder is heating up, the automatic air inflator must be turned off. If the air is too large during operation, the cylinder door should be opened to eliminate the air to prevent the air from falling due to excessive air. If cloth, roll, or bottom pressure occurs, adjust the pumping pressure to 2-3, and adjust the front and rear showerheads to 3, 4, 5, 6, and 7 correctly.
8. When making a flat knitting machine, the cylinder must be straightened and must not be semi-twisted to avoid creases, and the fabric must be inserted in the specified direction.
9. When making woven fabrics, mercerized cloths, and artificial cotton into the vat for boiling and bleaching, be sure to wrap them in pig cages to prevent slipping, which may cause friction and marks.
10. The cloth should be stretched for 30-50 seconds. Raise the temperature to 50℃ to make the cloth fully wet before using the thinning agent. Use a ladle to slowly apply the cloth along the inner wall of the cylinder. Never touch the fabric directly when adding slowly.
11. When cooking cloth for heat preservation, it is necessary to add dyeing auxiliaries such as HAC and dyes to the single-pass additive material room.
12. After the boiling cloth has been kept warm, it must be neutralized by HAC. This HAC cannot be taken too early because it will volatilize [HAC 0.9% 60℃×10′ 〕Measure the pH value to be 6.5-7.5.
13. After HACPH is OK, use the deoxidizing enzyme ENZYME 0.02g/l, let it cool for 15 minutes, and measure the H2O2 content (fetch water and bring it to the office for testing)
14. After each vat of cloth is boiled, it must be cut into A4-sized pieces. The whiteness directly affects the color combination and the light-sensitive color combination. Color, brightness, and depth.
15. Normally, it takes 150 minutes to cook cloth, so all links must be operated quickly and cannot be delayed, otherwise the progress and output will be affected.
16. The operating conditions of each cloth boiling process should be recorded (written by the team leader).
17. All additive barrels must contain additives by category.
4. Dyeing operation specifications.
1. Check lap time , a normal circle is 2’30”, if it exceeds this range, you should raise your hand to the superior, and pull the cylinder for 30″-50″ seconds.
2. Observe whether there are any Twist the cloth, check whether there is poor air pumping (air pumping cylinder), and whether various valves are closed.
3. Confirm the dyeing procedure and select the worksheet according to the requirements. After selecting, the technician or The team leader also wants toInspection. When checking the water level, be sure to stop the main pump and let the water stabilize in the water gauge. To check the paint, you need to use a sample (that is, generally use a piece of paper to test the color of the water). Only when the color matches, can it be dropped into the vat for dyeing: Help The agent should be checked to see if the quantity is too small or too large, and whether the quality and name are consistent with those on the order. The above inspections are correct, and the team leader signs for confirmation.
4. The dye can only be bathed in clean water in the auxiliary tank, not hot water or steam.
5. The time when the dye is pumped into the tank must be pumped in according to the computer programmed, neither too fast nor too slow.
6. When pumping in dye, if the machine is not running smoothly, stop feeding and raise your hand to the superior to handle it.
7. After the dye is cooled for 5 minutes, start adding salt [Nacl, Yuanming powder].
8. Normally, Yuanming powder is divided into four times. Each portion is added according to the requirements of the work order. It usually takes 40 minutes to pump the Yuanming powder into the tank. After adding Yuanming powder Na2SO4 After five minutes, take the dye solution to the office to measure the density and specific gravity of the dye solution. It is strictly prohibited to measure the density by yourself. There is a dedicated person. If the specific gravity is not OK, the colorist will decide to add water or additives. After adding, measure the specific gravity again until it is OK. until.
9. After the specific gravity is OK, add Na3PO4 or Na2CO3, the number of times is the same as that of Yuan Mingfen.
10. After adding dye additives, pay attention to the foaming situation. If the foaming is serious, use a defoaming agent to remove the foam. The use of FFC must be approved by the workshop foreman. .
11. For dyeing heating and heat preservation, the heating rate of 50℃ is 0.5℃/min, and the heating rate of 60℃ is 0.7℃/min. The holding time should be selected according to the time specified on the sheet.
12. Add dyes and additives during the heat preservation period, and the machine must be running normally, otherwise it will easily cause dyeing defects.
5. Post-processing and others
1. Keep warm Finally, it needs to be neutralized by HAC, 50℃×10′ 0.5g/l HAC. Do not take this HAC too early, as its characteristic is volatile.
2. After HAC neutralization, the next step is to boil alkali twice in hot water 95℃×10′. The purpose is to wash away the floating dye residue on the cloth. For a tub shower, you need to boil the shower head for the first time after boiling hot water.
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