摘要:挤压机广泛应用于硬质合金、制药、食品工业和机械加工等诸多领域。我们可以利用硬质合金挤压成型技术，来生产截面积较小且长度较长的产品。由于采用挤压技术可以获得长度方向上密度均匀的产品，并且生产效率高。因此在硬质合金机械加工中挤压技术得到普遍应用。

　　　食品挤压机类型有很多，目前，用于食品工业中的挤压机是螺杆挤压机，它主要由套筒以及在其上旋转的带螺旋的螺杆和滤网组成。而滤网孔的大小决定了所生产出的产品的种类。

　　　挤压系统是挤出成型设备设计的一项关键环节，而螺杆的结构设计和它的几何参数设计合理与否就是直接影响挤压系统的挤压过程，所以，螺杆是这个挤压系统的关键。

　　　本系统的设计包括螺杆的设计，控制系统的设计，PLC编程方面的技术问题，采用螺杆机筒的组合方式，通过两者对物料的摩擦来输送物料，并形成一定的压力来实现对粉末状原料的挤压加工，一般情况下，原料与机筒之间的摩擦系数大于原料与螺杆之间的摩擦系数，否者的话，物料包裹在螺杆上，和螺杆一起转动而起不到向前推进的作用。

关键词：单螺杆挤压机 螺杆设计 挤压加工 PLC编程 变频控制

ABSTRACT:Extrusion machine is widely used in the cemented carbide, pharmaceutical, food industry and machinery processing etc.. We can use the extrusion molding technology of hard alloy, to produce a smaller cross-sectional area and the length of long products. Due to the adoption of extrusion technology can obtain the length direction of homogeneous products, and high production efficiency. Therefore in the machining of hard alloy extrusion technology has been widely applied.

　　　There are many types of food extrusion, machine at present, extruder for the food industry is a screw extrusion machine, which is mainly composed of the sleeve and the rotating screw screw and. Sort and filter mesh size is determined by the production of the product.

　　　Extrusion system is a key link in the design of extrusion molding equipment, extrusion process, and the structure design of the screw and its geometric parameter design is reasonable or not is directly influence of extrusion system so, screw is the key of the extrusion system.

　　　The system design includes the design of screw, the design of the control system, the technical problems of PLC programming, using the combination method of screw and barrel, through both the friction of the material to transport materials, and formed a certain pressure to the extrusion processing of powder raw materials, under normal circumstances, the coefficient of friction between the material and the machine cylinder is larger than the friction coefficient between raw material and a screw, or words, material wrapped in the screw, and the screw to rotate together and not to the forward role. 

Keywords:  single-screw extrusion machine；Screw design；Extrusion craft；PLC programming；Frequency conversion control