1·Forming force during backward extrusion of hollow billet was analyzed by slab method and numerical simulation.
采用主应力法与数值模拟相结合的方法，研究分析空心坯料反挤压成形力变化规律。
2·Metal flow is a very inhomogeneous process during backward extrusion of complex box body, Relative shape and size of the blank is a key factor which affect metal flow.
复杂盒形零件的反挤压是一个极其不均匀的流动过程 ，坯料的相对形状及尺寸是影响金属流动的关键因素。
3·By improving the design of forging die and using press-forging and backward extrusion principle, solves the problems of 130 steering knuckle forming which can not be fully filled during forming.
通过改进预锻模膛的设计，利用镦粗成型、反挤成型的原理，有效解决了130转向节板部模锻成型时充不满的问题。
4·The multi-way tube joint were manufactured with advanced hydraulic extrusion-bulging forming replacing backward working methods.
采用先进的液压挤胀成形代替落后的加工方法生产多通管接头。
5·A method of hybrid inference based on forward inference and backward inference strategies is achieved in designing extrusion step analysis expert system.
采用正向推理与反向推理相结合的方法，开发了用于挤压工步分析专家系统的混合控制策略。