How To Choose The Screw Of The Plastic Extruder?

How to choose the screw of the plastic extruder?


In order to meet the needs of different plastic processing, there are many types of screw structures, and there are three common ones: gradient type (unequal depths), gradient type (unequal depths), mutation type, torpedo head type, etc. Next, let's take a look at how to choose the screw of the plastic extruder.

The main component of the plastic extruder is the screw barrel, which also has an important influence on the plasticization, extrusion, and molding of the plastic. Therefore, the reasonable selection of the rod structure and parameters is one of the prerequisites for obtaining the quality star and output of the ideal product. In order to meet the needs of different plastics processing, there are many types of butterfly rod structures, and there are three common ones: gradient type (consistent depth unequal depth or equal depth unequal depth), mutation type, torpedo head type, etc. So, how to choose the screw of the plastic extruder?

The selection of the screw structure of the plastic extruder is mainly determined according to the physical properties of the plastic and the production technical specifications of the extruder.

1. The softening of non-crystalline polymer is completed in a relatively wide temperature. Generally, equal-distance variable screw is used. The melting temperature range of crystalline polymer is relatively narrow, and isometric abrupt screw is generally used.

2. On small plastic extruders, such as the o45 extruder screw adopts a full-threaded type with equal intervals and unequal depths. The length of the screw is relatively small, and it is mainly used for extruding small cross-section insulation and sheath layers. The extrusion speed is faster. 3. The medium-sized screw adopts a full-thread type with equal pitch and gradually changing thread depth. Its length-to-diameter ratio is larger than that of a small screw, and the pitch of the threads is equal, starting from the root from shallow to deep. The thread at the end of the thread is deeper and the thread at the root is shallow

In this way, the amount of plastic extrusion is more, but not

Influencing the strength of the screw, the extrusion speed is fast, and the plastic is well plasticized. It is an ideal screw for the production of insulating and sheath layers on general small and medium extruders.