Paper Tray Specific Production Process

The first step: smashing and beating
The waste paper or grass product pulp board is put into a hydropulper and re-pulverized into pulp. Horizontal hydraulic pulpers are commonly used in the production of industrial packaging products, and the pulp concentration during disintegration is 5% to 8%. The utility model has only the dispersing effect on the paper fiber, has no cutting effect, high disintegration efficiency, short disintegration time, less power consumption, simple structure, small floor space, and can handle more dopants and metal impurities. Waste paper. The disintegrated pulp falls into the storage tank, is adjusted to the appropriate concentration, and is pumped into a batch beater or a continuous refiner, beaten on the refiner, or the pulp is disintegrated according to production needs. After high concentration slag remover, fiber disintegration machine and double disc refiner for slag removal, spalling and beating, the prepared slurry is discharged to the storage tank or the matching pool for use. The degree of beating degradation is generally 28 degrees – 35 degrees.
The second step: blending the slurry
In the process of beating, several raw materials can be quantitatively added to the slurrying tank according to the designed slurry ratio, and the slurry is sized and a small amount of functional auxiliary agent is added. If a sizing agent is added to improve the liquid permeation resistance of the paper molded article, the sizing agent used is generally rosin, paraffin latex or rosin paraffin glue. It is worth mentioning that after adding the additive, the product cannot be called environmentally friendly paper tray. For the non-bonded waste paper pulp, it is necessary to add rosin gum equivalent to 3% of the pulp dry fiber quality; For product pulp, 1.5% ~ 2% rosin should be added. In the pulp, talcum powder can be added as a filler to achieve a relatively high slurry retention rate. The water suspension containing 20% ​​to 30% of talc filler can be treated in a stirrer for 6 minutes at high speed, diluted with water and then added with chemical aid. The agent was further treated for 5 minutes to prepare a filler suspension, which was then added to the slurry. Some manufacturers have also added a small amount of anti-oil agents, water-repellent agents, wet strength agents and retention aids to the slurry. In the pulping process, an appropriate amount of white water or water is added to adjust the pulp loading concentration of the molded product to 1% to 2%.
The third step: paper molding
Molding is a key process in the production process of paper trays. It plays a decisive role in the quality, breakage rate, production energy consumption and production efficiency of paper mold products. According to the dehydration principle of the molding equipment, there are three main methods for forming the paper tray: vacuum forming method and hydroforming method.
The vacuum forming method is formed by vacuum suction filtration technology. The forming mold is placed in a pulp solution having a concentration of about 1%, and a vacuum is formed in the cavity of the mold to form a negative pressure, and the fibers in the pulp are uniformly deposited on the surface of the molding die. On the mold web, a large amount of moisture is taken away during vacuum suction. When the thickness required for the workpiece is reached, the molding die is removed from the slurry for extrusion dewatering until the moisture content of the workpiece is 75% to 80%, and the compressed air is passed through the cavity to demold the wet paper mold. This method has high production efficiency and uniform thickness, and is suitable for making thin parts that are not too deep, such as paper trays for packaging eggs, fruits, saucers, and trays.
The hydroforming method uses hydraulic technology to produce high extrusion pressures by hydraulically driven mechanical devices. The working principle is that the quantitative pulp is injected into the molding cavity, and the forming upper die is pressed downward under the action of hydraulic pressure to make the pulp form on the mesh mold in the molding cavity, and the water is discharged from the lower end of the mesh mold. The parts are vacuum-desorbed and transferred to the next process. Due to the high molding pressure, this method is suitable for the production of shallow disc products with heavier weight and higher density.
From Best Plus Pulp www.bestpluspulp.com We manufacture and customize the Pulp Paper Tray and Cartons, Shoe Pulp Tray, Egg Tray, Egg Cartons, Pulp Basket, Wine Pulp Tray and other customized Pulp packaging products.