第42卷第5期 Vol. 42No. 5
假压技术
FORGING & STAMPING TECHNOLOGY
消除厚板件折弯时表面压痕的方法与模具研发
吕浩源
（中车长春轨道客车股份有限公司工程技术中心，吉林长春130062）
2017年5月 May 2017
摘要：介绍了厚板零件在折弯成形时其外表面产生压痕的现状和处理方法，以及已有技术在解决板料折弯压痕方面的局限性，论分析的基础上，开发出能够适用于厚板料、大角半径的折弯零件的半轴翻板式无压痕折弯模。从运动力学角度，给出了模具的其体结构尺寸与其适用范围之间的关系。通过实际应用，验证了这种新结构的模具非常有效，完全消除了厚板折弯件表面的压痕衰，改善了折弯件的表面质量，提高了生产效率，降低了生产成本。
关键词：厚板件；折膏；表面压衰：半轴翻板式折弯模；常规凹模 DOI: 10. 13330/j. issn. 1000-3940. 2017. 05. 019
中图分类号：TG386
文献标识码：A
文章编号：1000-3940（2017）05-0102-06
Method of eliminating surface impressioninthe bendingof
thick plate parts and die development
Lyu Haoyuan
( Engineering Technology Center, Changchun Railway Bus Co. , Lid. , Changchun 130062 , China)
Abstract : It was introduced the current situation and handling method of outer surface impression in the bending of thick plate parts, and the limitation of existing technology in solving the bending impression was presented. Then, influential factors of impression and their rela tionships were described theoretically. Therefore , an innovative solution was put forward, and its feasibility was analyzed in detail. On the basis of the theoretical analysis, a semi-axis turning plate bending die with no-impression was developed to bend parts of thick plate and large fillet radius. Based on the kinematic mechanics, the relationship between specific structures with its application scope was pro vided. Through the practical application, it was proved that the die with a new structure could effectively eliminate the impression on ben-ding of thick plate parts and improve the surface quality. Therefore, the production efficiency was improved and the production cost was reduced.
Key words : thick plate part; bending; surface impression; semi-axis turning plate bending die; conventional die
铁路客车转向架上的零件，大部分料厚都在 10mm以上，很多采用折弯工艺[1-2]来成形，因变形抗力大，板料与常规凹模为线性接触，凹模的槽宽受到制件结构限制又不能过大，经常会在工件表面留下较深的沟痕，按照质量标准的要求，需进行手工打磨处理。压痕宽度一般在4~8mm，深度最大时可达0.8mm，为了保证圆滑过渡，打磨区宽度需要在30mm左右，这样傲即费工费时，又破坏了工件的表面状态，还减小了板料的局部厚度。
收稿日期：20170316；修订日期：20170420
基金项目：中车长客股份公司2015年技术开发项目（15(CZX0X2）
作者简介：吕浩源（1959-），男，学士，高级工程师 E-mail: hhaoyuan@ cccar,. com cn
万方数据
图1和图2分别为左右弯曲板和横梁下盖板压痕情况的实物照片。图3为横梁下盖板打磨后的实物照片。
1
现有技术
消除折弯件表面压痕的常用方法有[3-5：小型
翻转凹模、宽槽落柱凹模和凹模口加保护膜等，但都有一定的局限性。小型翻转凹模不适合厚板大圆弧件，保护膜也不能适合厚板件，而滚柱凹模则不适合弯曲线较长的工件，
目前还没有一种能够完美解决厚板大圆弧件折弯时压痕明显的成形方法。
图4为目前广泛应用的常规凹模。坏料与凹模