Spacing Characteristics Between Moving Permeable Web and Roller

在塑料片材、纸张、磁带、照相胶片等制造领域中，这些连续的柔性材料一般称为“卷筒纸”，常采用导辊支撑的卷筒纸输送系统。此外，除输送过程外，还包括卷筒网缠绕过程。在这样的系统中，估计腹板和导辊之间或卷绕腹板层之间的夹带气膜厚度（润滑气膜厚度）对于更好地理解虚构条件和提高腹板处理过程的效率是至关重要的。在腹板处理过程中，通常采用基于无限长宽度箔轴承理论的气膜厚度公式来估计夹带气膜厚度。然而，在腹板宽度较小的情况下，无限长轴承假设会在估计气膜厚度时产生一些定量误差。因此，需要更准确地估计气膜厚度，以考虑腹板宽度的影响。针对这一要求，最近，Hashimoto在可压缩雷诺方程和腹板弹性方程的数值解的基础上，以腹板宽度、腹板张力和腹板速度为参数，得到了估算腹板与辊间夹带气膜厚度的简便简化公式。然而，据作者所知，还没有发表过实验研究腹板宽度对腹板与辊间夹带气膜厚度影响的论文。实验研究了腹板宽度对导辊与腹板夹带气膜厚度的影响。在测量气膜厚度时，采用窄宽度的录音带和较宽宽度的纸张作为卷筒，并分别使用两种类型的试验台。测量了不同速度和腹板张力组合下的气膜厚度。将实测结果与基于Hashimoto推导的简化公式的计算结果进行了比较，并从理论上和实验上考察了腹板宽度对气膜厚度的影响。少

In the manufacturing fields of plastic sheet, paper, magnetic tape, photographic film etc., these continuous flexible materials are generally called "web", and the web transporting systems supported by the guide rollers are often used. Moreover, in addition to the transporting processes, the web winding processes are included in the systems. In such systems, it is of cardinal importance to estimate an entrained air film thickness (lubricating air film thickness) between web and guide roller or between layers in the wound web for better understanding the fictional conditions and for improving the efficiently of web handling processes. The air film thickness formula based on the infinitely long width foil bearing theory is usually used for the estimation of entrained air film thickness in the web handling processes. However, in the case of small web width, the infinitely long bearing assumption will cause some quantitative errors in the estimation of air film thickness. Therefore, it has … More been required for more accurate estimation of air film thickness to take into account the effects of web width. For such a requirement, Hashimoto obtained recently the convenient simplified formula for the estimation of entrained air film thickness between web and roller, which includes the web width, web tension and web velocity as parameters, based on the numerical solutions of compressible Reynolds equation and web elastic equation. However, as far as the authors know, there is no published paper examining experimentally the effects of web width on the entrained air film thickness between web and roller.In this research work, the effects of web width on the entrained air film thickness between web and guide roller were examined experimentally. The narrow width of audio-tape and the relatively wide width of paper were used as web in the measurements of air film thickness and two types of test rigs were used for each case. The air film thickness was measured for various combinations of velocity and web tension. The measured results were compared with the calculated results based on the simplified formula derived by Hashimoto and the effects of web width on the air film thickness were examined theoretically and experimentally. Less