Extruderworking Principle

The extruder can be divided into continuous extrusion and discontinuous extrusion according to the type of action. According to the angle between the head flow direction and the screw centerline, the machine head is divided into bevel head (angle 120 °) and right angle head The The head of the nose is fixed with bolts on the fuselage, the die inside the mold has a core sitting, and fixed with a nut in the nose into the line port, the front of the core seat with a core, core and core The center has holes for passing through the core. Plastic extruder is also a kind of plastic machinery.

Plastic extruders are also one of the types of plastic machinery. Extruder according to the direction of the head material and the angle of the screw center line, the machine can be divided into right angle head and bevel head and so on. The head of the head is usually bolted to the fixed on the fuselage, the head of the mold inside the mold core seat, and then use the nut to be fixed in the nose of the nose port, the core of the core is also equipped with And the center of the mandrel and mandrel has holes, which act on the core. Depending on the type of pressurization, the extrusion process can be divided into two types: continuous extrusion and intermittent extrusion. The former equipment used for the screw extruder, the latter equipment for the plunger extruder. In this screw extruder can be roughly by virtue of the number of screws for the single screw extruder and multi-screw extruder.

The working mechanism of the screw extruder depends on the pressure and shear force generated by the rotation of the screw, which allows the material to be fully plasticized and homogeneously mixed and molded by die; sometimes it can be done simultaneously using an extruder Mixing, plasticizing and forming a series of processes, so as to continuous production. In addition, the working mechanism of the plunger extruder is mainly by the use of plunger pressure, the first plastic material in advance from the die extrusion to achieve the effect of forming. The material in the material cylinder will be returned after extrusion, until the next round of plasticizing material is added and then the next round of operation is carried out. As well as the mixing, in addition to the production of pre-plasticization, so in the actual production is usually not often used in this law, can only be applied to the poor mobility or viscosity is very large plastic, like nitrocellulose plastic this Plastic products of the molding process. The plastic extruders can be categorized as twin screw extruders, single screw extruders, and rare multi-screw extruders and screwless extruders.

Plastic material from the hopper into the extruder, driven by the rotation of the screw to move forward, the material in the forward movement of the process, to accept the barrel of the heating, the screw to bring the shear and compression of the material so that the material melting , Thus realizing the change between the three states of the glassy state, the high elastic state and the viscous flow state.

In the case of pressurization, the material in the viscous state passes through a die having a certain shape and then becomes a continuum of cross-section and die-like pattern according to the die. And then cooled and shaped to form a glassy state, thereby obtaining the desired processing.