摘 要:本设计所设计的是拖拉机底盘固定支架的成形工艺和模具设计。主要是设计一套简便、经济以及适用的模具能很好的完成产品的生产要求。由于工件尺寸未注明公差IT14，模具可按IT11制造，尺寸精度和形状精度要求低，普通冲裁完全能满足要求。本设计采用自动化程度高、生产规模大的级进模，分解落料模、拉深模、切舌模和冲孔模的特点和需要注意的问题，在模具简图的基础上进行模具结构工艺性分析，进行模具结构设计并选择冲压设备。

　　　使用级进模可以减少压力机，减少半成品的运输。车间面积和仓库面积可大大减小。

级进模的缺点是结构复杂，制造精度高，周期长，成本高。因为级进模是将工件的内、外形逐次冲出的，每次冲压都有定位误差，较难稳定保持工件内、外形相对位置的一次性。但精度高的零件，并非全部轮廓的所有内、外形相对位置要求都高，可以在冲内形的同一工位上，把相对位置要求高的这部分轮廓同时冲出，从而保证零件的精度要求。

关键词：拖拉机固定支架； 切舌； 弯曲; 连续模具设计

ABSTRACT:This design is the forming process of tractor chassis fixationAnd mould design。Production is mainly designed a set of simple, economical and suitable mould could make the complete of the production。Because of the size of the workpiece is not tolerance，so just make it in IT14。The mold can use the  manufacturingin in IT11. The requirements of dimensional accuracy and shape accuracy is Low.nomal conventional blanking is Fully able to meet the requirements.The design use a high degree of automation, large-scale production of progressive dies.Decomposition characteristics of blanking die, drawing die, lancing die and punching die and some problems of the process analysis, mold structure based on the die drawing, die structure design and stamping equipment selection.

　　　The Use of progressive die can reduce press, reduce the transportation of semi-finished products. The area of the workshop and warehouse area can be greatly reduced. Progressive die is of complicated structure, high manufacturing precision, long period, high cost. Because of the progressive die is the workpiece in successive, shape out, each time stamping has positioning error, difficult to maintain stable disposable, the relative position of the workpiece contour. But the high precision parts, not all contour, shape the relative position of all requirements are high, can be the same station in the profile, the relative to the part contour location requirements high at the same time out, so as to ensure the precision parts.

Keywords：tractor fixed bracket；lancing die;Bending;Mould design