挤压模具设计书说明书标题.doc

铜合金压气缸的热挤压工艺及模具设计 摘 要 铜合金压气缸的生产方法常见的有管料的切削加工，离心铸造后切削加工，热挤压法。热挤压法生产材料利用率最高，生产效率最高，产品质量最高。本文分析热挤压工艺及模具设计。 热挤压工艺分析综述：铜合金的热挤压温度根据经验可以定为730℃。压气缸的毛坯件属于杯形件的一种，因此采用的是反挤压。若采用一次挤压成形则所需挤压力和变形程度太大。因此采用两次反挤压，第一次将棒料挤压成为杯形件，切削加工成空心圆柱形。再经过第二次反挤压将内孔扩大，外径不变。经过两次反挤压得到挤压件成形毛坯。 模具设计分析综述：两序挤压则需要两套挤压模具。两套模具采用通用凹模，结构简单。第一套模具凸模采用一般的反挤压凸模结构。第二套模具需要有模芯结构，模芯可以是固定式的也可以是活动式的。本次设计将模芯设计为固定式的即凸模和模芯一体式的。设计成整体式的好处是结构简单，生产效率高。与此同时，顶件器只需设计成中空的即可，当凸模压下时，模芯正好进入顶件器的内腔中。 关键词：反挤压，压气缸，模具设计，模芯 Copper Alloy Cylinder Pressure of Hot Extrusion Technology and Die Design ABSTRACT Copper alloy pressure cylinder production methods common pipe material cutting processing, machining after centrifugal casting, hot extrusion method. Hot extrusion method is the highest utilization rate of materials, the highest production efficiency,and the highest quality of product . In this paper, hot extrusion technology and die design is analysed. Hot extrusion technology analysis were reviewed: Copper alloy can be classified as 730℃ hot extrusion temperature according to the experience. Pressure cylinder of a blank parts belong to the cup, so the backward extrusion is used. If using an extrusion forming ,the needed extrusion and deformation degree is too large. so the backward extrusion shoud be used twice.The first extrusion will make the bar become the cup, and then, make the cup become the hollow cylindrical by machining. After second backward extrusion will enlarge the inner hole, and the outside diameter is constant.After twice backward extrusion,we can get the bloom. Mold design analysis were reviewed: The two order squeezing requires two sets of extrusion dies Two sets of mould adopt general concave die. The first set of mould punch adopts general backward extrusion punch die structure. A second set of mould need a mold core structure, mold core can be stationary or activities. This design will design for fixed the punch mold core and mold core one-piece. Design into integral advantage is simple structure, high production e