The Study Of Ring Crush Strength Of Corrugating Medium

This paper want investigate the influencing factors and the law of the ring crush strength of corrugated medium under not considering surface sizing condition. Wide data acquisition lays the foundation for establishing a data model of the ring crush strength of corrugated medium under not considering surface sizing condition. The irregularity data makes establish a data model of the ring crush strength of corrugated medium more difficult. This study has guiding significance and reference value for the production and scientific research of corrugated medium.Firstly, the research investigate the influencing factors of the ring crush strength of corrugated medium influenced by pulp raw materials, fine fiber, beating. Waster paper pulp with complicated composition lead to unsatisfying repeatability of results. It has no guiding significance. So electing softwood bleached kraft pulp, reed bleached chemical pulp and waste paper pulp as the experiment object. The change of the properties of pulp and paper are investigated in the fiber recycling respectively. And the possible ways to improve the ring crush strength of corrugated medium were investigate.In the experiment, the fine component of waste paper pulp is seriously lost(about 17%, broken fine fiber and amorphous cellulose fiber) in the papermaking process and the ring crush strength of paper is as low as 4.74N·m/g.The bonding force between fiber is the main influence factor on the ring crush strength of corrugating medium strength. The combination of the fiber is more closely with the bonding force between fiber increasing, so the paper ring crush strength is increased. The retention of fine component has important significance for the production of corrugating medium. CS+CP3+CPAM is the optimal retention and drainage system for keeping fines, the best amount of component that CS is1.0%, CP3 is 0.003%, CPAM is 0.03%. The quantitative increased by 12.7%, the ring crush index increase by 40.7%. The retention of small fibers makes the combination of the fiber more closely and increases the bonding force between the fiber, which increased the ring crush strength of paper.It shows that properly beaten waste paper pulp contributes to improving the ring crush strength of corrugated paper with the bonding force between fiber increasing. Waste paper pulp it beaten by PFI. When beating excessive, fibers are broken and fractured by excessive beating, making the paper strength reduced. When freeness is 380 mL, the ring crush index increases by 30.3%.According to the respective recycle experiments of the softwood bleached kraft pulp, reed bleached chemical pulp and waste paper pulp, we conclude that the average length of fiber is decreased.The proportion of amorphous region of the fiber decrease and The proportion of the crystalline region increase, which lead the fibrillation of fiber to hard. The fiber bonding force is reduced, which makes the paper strength reduced.Calendaring makes paper be tight, as while as destroys the porous structure between fibers which results in the loss of the ring crush strength of corrugated medium.Deflaking is conducive to reducing the freeness of pulp. Deflaking makes the fiber dispersed more easily with less damage and increases the ring crush strength.Low-cost compound alkali can replace sodium hydroxide to regulating the pH value of white water, which is favorable to the waste water treatment, reducing the corrosion of paper machine and reducing cost.