Plastic extrusion equipment - gate
PVC plastic extrusion supplier shares that it is the channel through which the mainstream (or shunt) is connected to the cavity. The cross-sectional area of the channel may be equal to that of the main flow channel, but is usually reduced. So it's the smallest part of the whole flow system. The shape and size of gate have great influence on the quality of products.
The role of the gate is:
A. control material flow speed:
B. During the injection, the molten material stored in this part can be prevented from backflow due to early coagulation:
C. Make the molten material passing through subject to strong shear and increase the temperature, thereby reducing the apparent viscosity and improving the fluidity:
D. Facilitate the separation of products from the runner system. The shape, size and location of the gate depend on the nature of the plastic and the size and structure of the product. In general, the cross-section shape of the gate is rectangular or round, and the cross-section area should be small and the length should be short, which is not only based on the above effect, but also because it is easier for the small gate to become large, while the large gate to become small is difficult. Gate locations should generally be where wip is thickest without affecting appearance. The design of gate dimensions should take into account the properties of plastic melts. The cavity is the space in the mold for forming plastic products. Components used to form cavities are collectively referred to as molded parts. Each molding part often has a special name. Forming parts to form the shape of products called concave mold (also known as the negative mold), forming the internal shape of products(such as holes, slots, etc.) .
Known as the core or punch (also known as a male). When designing molding parts, the overall structure of the cavity should be determined according to the performance of the plastic, the geometric shape of the product, the dimensional tolerance and the use requirements. Secondly, the location of parting surface, gate and vent as well as the demoulding method are selected according to the determined structure. Finally, according to the size of the control parts of the design and determine the combination of the components. The plastic melt has high pressure when entering the mold cavity, so the molding parts should be selected reasonably and the strength and rigidity should be checked. In order to ensure the smooth and beautiful surface of plastic products and easy to demold, the surface in contact with plastic, its roughness Ra>0.32um, and corrosion resistance. Molding parts are generally through heat treatment to improve the hardness, and the choice of corrosion resistant steel manufacturing.
That's all for the sharing,and we supply Custom Pvc Plastic Extrusion Profile for sale, if you have any demand for our products,just feel free to contact us.