Requirements of equipment, process and technology

2022-07-26
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Requirements for equipment, process and technology of cold high strength and quick drying adhesive

1. mixer: rotating speed 60-80 rpm

2. when the adhesive viscosity is too low (less than 20 seconds) and the adhesive is also a translucent colloid, it is necessary to make a pot of adhesive with higher viscosity for mixing. Its performance is more and more environmentally friendly. You can also add an appropriate amount of starch paste (starch + water) to the adhesive, and then stir it evenly. The adhesive made by this method should not be stored for a long time

3. when the adhesive viscosity is too high and the glue throwing phenomenon occurs or the glue machine cannot be used (the viscosity of the adhesive in normal use has a certain relationship with the speed of the glue machine, the speed is slow, the viscosity can be appropriately large, the speed is fast, the viscosity can be appropriately small, and the principle is that it can work normally without glue), an appropriate amount of oxidant can be added to dilute it, that is, it can be oxidized again. Pay attention not to add water to dilute it, so as to avoid degumming and glue throwing

4. in order to prevent the viscosity of the adhesive from being too high or too low, it is better to make the adhesive with a higher viscosity without adding borax or boric acid too early, add caustic soda to the adhesive to be made for 2 hours or more, and measure its viscosity. If it is about 70 seconds, add an appropriate amount of water to dilute it to about 60 seconds, and then add borax to stabilize it for 30 minutes

5. when the adhesive is stored, it is best to store it in a sealed manner and not expose it to the air to avoid scaling

6. it is better if the temperature is above 8t in winter, otherwise the reaction time is too long, the operation is inconvenient, and the quality of adhesive will be affected

7. in the workshop using adhesive, the temperature in winter shall not be lower than - 5cc

8. it is better to control the glue consumption during sizing (single tile double-sided sizing) at 80-120g/m, too little is easy to degumm, and too much is slow to dry

9. in the process of breaking the bottleneck of raw materials in batch production, a small test shall be conducted for each change of raw materials to observe the ideal proportion and quantity of raw materials. During the small-scale test, it is better to make 4-5 small samples at the same time, and each small sample is formulated according to different proportions, so that the best formula proportion of the new raw materials and the ambient temperature and humidity at that time can be observed in a very short time, so as to avoid unnecessary accidents during mass production

10. in the production of starch adhesive: the viscosity must be adjusted according to the object of starch adhesive

① high strength corrugated paper, single-sided corrugated paper board and thin corrugated color box paper board compound adhesive, with viscosity of about 35 ± 10 seconds

② the viscosity of adhesive for ordinary corrugated paper is about 50 ± 10 seconds

③ the viscosity of adhesive for automatic veneering machine and honeycomb paperboard is about 70 ± 15

method for measuring the viscosity of adhesive:

place clean and dry 4 cups on the rack, adjust the horizontal screw to make the viscometer in the horizontal position, place 200m below the viscosity cup, first check whether the installation of the testing machine is horizontal l enamel cup, adjust the temperature of the tested sample to the required temperature, block the lower mouth with hands, and fill the viscosity cup with samples, Scrape the bubbles and excess samples into the groove with a glass rod, then loosen your finger to make the sample flow locate the four corners of the rectangular hollow pier with a total station, and immediately start the stopwatch. When the sample flow is interrupted, stop timing. In this way, the total time (s) flowing out of the viscosity cup is the conditional viscosity of the sample

note: for the structure of coated - 4 cup, the upper part is cylindrical, the lower part is conical, and there are grooves on the upper part of the container for excess sample overflow. The viscosity cup is mounted on a rack with two leveling screws. Coated - 4 cups are made of plastic and metal. The inner wall finish is 8. The metal viscometer shall prevail. The viscometer must be calibrated before use

11. when potassium permanganate is used as oxidant, caustic soda should be added twice. For the first time, 50-60% of the caustic soda amount should be added immediately after adding potassium permanganate, and for the second time, it should be added slowly after adding potassium permanganate for oxidation for 20-30 minutes, so as to avoid too thick gel state after adding caustic soda

12. after common corrugated paper and high-strength corrugated paper are applied on both sides, if there is edge and edge running, first check whether the corrugated fiber lines are parallel to the corrugated (the cross is the main reason for edge running), and then select the adhesive with high starch content, and try to reduce the amount of sizing, subject to no degumming

13。 During the use of starch adhesive, if the conjunctiva is too fast and the corrugated board is not pressed by the press, part of the conjunctiva will be degummed, so the amount of desiccant must be reduced according to the situation

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