radius of bending

By analyzing the wide sheet bending, the variations of theoretic radius values of outer surface, sheet thickness and thinned coefficient with radius of inner surface in bending were put forward. The results were compared with testing data and approximate values.

对宽板弯曲变形过程进行分析，提出了弯曲过程中板坯外表面半径，板料厚度和变薄系数随板坯内表面半径变化的理论解，并与查表法和近似解作了比较。

In the NC bending process of thin-walled tube with small bending radius, the maximal hoop strain can reach 1/ 3 of the tangential strain and can not be neglected.

薄壁管小弯曲半径数控弯曲成形中，周向应变不可忽略，其值最大可达最大切向应变的1/3；

Tube bending is a process by which a straight piece of tube is formed to a selected radius and angle of bend.

弯管工艺是指将平直的管子按选定的半径和弯曲角度弯曲成形。

Under the conditions of the same internal pressure, with the relative bending radius increased, ellipticity and the thickening rate of internal measuring point decreased; the thickening rate of outer measuring point gradually were also decreased.

在充液压力相同的条件下，随着相对弯曲半径的增加，椭圆度逐渐减小；内侧点的增厚率逐渐减小；外侧点的减薄率逐渐减小。

The determination of the minimum bending radius in the design of the pipe_bending die was stated. And the structure of the die slot, the form and installation of the shaft core were introduced. The pipe was prevented effectively from deformation.

叙述了弯管模设计中最小弯曲半径的确定，弯管模模槽的结构，芯轴的形式和安装，有效地防止管子变形，并通过实践经验给出了一些模具设计参数。