extension ratio meaning in English

拉伸比
伸长比

By means of geometric analysis of belt deformation in transition section , the paper introduces how to calculate the length in transition section , with considering extension ratio of belt and the difference between head a and tail of extension section
本文通过对过渡段输送带变形的几何分析，综合考虑输送带伸长率以及头尾过渡段区别，给出圆管带式输送机过渡段长度的理论计算方法。