Conical Twin Screw and Barrel
Cold Feed Rubber Machine Screw and Barrel manufacturers take you to understand the structure of the barrel
Cold Feed Rubber Machine Screw and Barrel manufacturers tell you that the barrel, like the screw, is an important part of the extruder in the extrusion and compression molding system. The barrel and the screw work together, the barrel accommodates the screw, and the screw rotates in the barrel. Cold Feed Rubber Machine Screw and Barrel manufacturers tell you that when the screw rotates and pushes the plastic to move forward in the barrel, the external heating of the barrel conducts heat to the plastic in the barrel, and the thread volume on the screw gradually shrinks, making the thread groove The plastic inside is uniformly mixed and plasticized under the action of various forces such as extrusion, flipping and shearing. As it moves to the front of the barrel, it gradually melts into a viscous fluid state to complete the plasticization of the plastic. The normal cooperation between the barrel and the screw ensures the continuous extrusion of raw materials for the extruder.
Common barrel structures are integral, segmented, bushing and bimetallic.
(1) Integral structure barrel: Cold Feed Rubber Machine Screw and Barrel manufacturers tell you that the integral structure barrel is widely used in extruders, especially when the size of the extruder is small, the integral barrel is generally used . The arrangement of the heating and cooling devices for the barrel is convenient, the temperature control is easy to ensure, and the machining accuracy of the barrel is high.
(2) Segmented structure barrel: The segmented structure barrel is mainly used in larger size extruders and vented extruders. Cold Feed Rubber Machine Screw and Barrel manufacturers tell you that because the barrel is divided into several sections, the length of each section of the barrel is small, which brings convenience to machining; however, the inner diameter size and concentricity accuracy of several sections of the barrel It is difficult to achieve unity; in addition, the segmented barrels are connected with flanges, which brings certain difficulties to the arrangement of the heating and cooling devices of the barrels, and the temperature control of heating and cooling will not be too uniform.
(3) Bushing or casting wear-resistant alloy on the inner diameter of the barrel: In order to save precious alloy steel, the barrel of the larger extruder is usually formed by cast steel, and then a wear-resistant alloy bushing or a wear-resistant alloy bushing is added after finishing the inner hole. Cast a layer of wear-resistant alloy material.
The application of bushing barrels or casting a layer of wear-resistant alloy barrels in large extruders not only saves a lot of precious alloy steel and reduces equipment manufacturing costs, but also creates convenient conditions for future barrel maintenance. : Cold Feed Rubber Machine Screw and Barrel manufacturers tell you that when the barrel alloy bushing is severely worn, just replace the bushing to make the barrel work normally, saving equipment maintenance time.