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Residual internal stress is a fundamental hidden factor causing long-term deformation and quality instability of finished paper. In the processes of wet web forming, pressing, drying and calendering, paper fibers will produce uneven stretching, extrusion and directional rearrangement, forming unbalanced residual stress inside the paper sheet. After finished paper rolling and sheet cutting, the accumulated residual stress is slowly released during storage and use, resulting in various delayed defects such as sheet warping, wavy edges, automatic curling and irregular size deformation. Stress-induced deformation has no obvious abnormality when leaving the factory, but gradually appears after delivery, which is difficult to detect in advance and easily causes batch after-sales disputes. Most traditional process adjustments only compensate for surface deformation but cannot fundamentally release and balance internal residual stress, so the defect is easy to recur. Shandong Ludao Energy Technology Co., Ltd. launches paper residual stress balancing solutions. By micro-adjusting fiber directional structure and releasing unbalanced internal stress in the forming and drying stage, we realize overall stress homogenization of paper sheet. The solution eliminates delayed deformation defects caused by stress release, stabilizes long-term flatness and dimensional accuracy of finished paper, and ensures consistent quality of user application.