When winding up the film, due to the action of tension and pressure of the roller, its shaft bottom. The branch is subjected to a very large internal pressure, prone to wrinkles and deformation. The effect of attenuation is to reduce the relative winding tension and roller pressure as the winding diameter increases.

The attenuation curve is generally based on the winding diameter and winding tension. The greater the attenuation value, the faster the tension will decay, and the smaller the internal pressure under the same tension pressure. According to different materials, the selection of appropriate tension, pressure and attenuation values plays a key role in reducing the wrinkles of the shaft bottom.