What is a plastic mold? Plastic molds are tools used in the plastic processing industry that are matched with plastic molding machines to give plastic products complete configurations and precise dimensions. Simply put, a plastic mold is a tool used to process plastic.
Due to the wide variety of plastic varieties and processing methods, and the complex and simple structures of plastic molding machines and plastic products, the types and structures of plastic molds are also diverse. Mainly divided into the following 6 types.
- Plastic injection (plastic) mold
It is mainly the most commonly used molding mold in the production of thermoplastic parts. The processing equipment corresponding to the plastic injection mold is a plastic injection molding machine. The plastic is first heated and melted in the heating barrel at the bottom of the injection machine, and then is heated and melted in the screw of the injection machine. Or driven by a plunger, it enters the mold cavity through the injection machine nozzle and the mold’s gating system. The plastic is cooled and hardened to form, and the product is demolded to obtain the product. Its structure usually consists of molding parts, pouring system, guide parts, push-out mechanism, temperature adjustment system, exhaust system, support parts and other parts. Manufacturing materials usually use plastic mold steel modules. Commonly used materials are mainly carbon structural steel, carbon tool steel, alloy tool steel, high-speed steel, etc. The injection molding processing method is usually only suitable for the production of thermoplastic products. Plastic products produced by the injection molding process are very wide, ranging from daily necessities to various complex machinery, electrical appliances, transportation parts, etc., are all molded with injection molds. It is the most widely used processing method in the production of plastic products.https://solidcomould.com/product/armrest-8/
- Plastic compression mold
It includes two structural mold types: compression molding and injection molding. They are a type of mold mainly used to shape thermosetting plastics, and their corresponding equipment is a pressure forming machine. The compression molding method heats the mold to the molding temperature (usually 103°-108°) according to the characteristics of the plastic, then puts the measured compression molding powder into the mold cavity and feeding chamber, closes the mold, and the plastic is heated under the action of high heat and high pressure. It appears as a softened viscous flow, and after a certain period of time, it solidifies and becomes the desired product shape. The difference between injection molding and compression molding is that there is a separate feeding chamber. The mold is closed before molding. The plastic is preheated in the feeding chamber and becomes a viscous flow state. It is adjusted and extruded into the mold cavity under pressure and hardened to form. Compression molds are also used to form certain special thermoplastics such as difficult-to-melt thermoplastics (such as polyethylene fluoride) blanks (cold press molding), resin lenses with high optical properties, slightly foamed nitrocellulose car steering wheels, etc. . The compression mold is mainly composed of a cavity, a feeding cavity, a guide mechanism, an ejection component, a heating system, etc. Injection molds are widely used in packaging electrical components. Compression molds are made from basically the same materials as injection molds.https://doi.org/10.1016/j.jmapro.2023.03.072
- Plastic extrusion mold
A type of mold used to produce continuous-shaped plastic products, also called an extrusion molding head, is widely used in the processing of pipes, rods, monofilaments, plates, films, wire and cable coatings, special profiles, etc. The corresponding production equipment is a plastic extruder. The principle is that solid plastic is melted and plasticized under the conditions of heating and screw rotation and pressure of the extruder, and is made into a cross-section with the same shape as the die through a die of a specific shape. Continuous plastic products. Its manufacturing materials mainly include carbon structural steel, alloy tools, etc. Some extrusion molds are also inlaid with diamond and other wear-resistant materials on the parts that need to be wear-resistant. The extrusion process is usually only suitable for the production of thermoplastic plastic products, and its structure is significantly different from injection molds and compression molds.
- Plastic blow mold
It is a mold used to form hollow plastic container products (such as beverage bottles, daily chemical products and other packaging containers). According to the process principle, the main forms of blow molding include extrusion blow molding and injection blow molding. , injection stretch blow molding (commonly known as “injection stretch blow molding”), multi-layer blow molding, sheet blow molding, etc. The equipment corresponding to the blow molding of hollow products is usually called a plastic blow molding machine. Blow molding is only suitable for the production of thermoplastic products. The structure of the blow mold is relatively simple, and the materials used are mostly made of carbon.
- Plastic blister mold
It is a kind of mold that uses plastic plates and sheets as raw materials to form some relatively simple plastic products. Its principle is to use the vacuum opening method or the compressed air molding method to make the plastic plates and sheets fixed on the concave mold or punch mold. When heated and softened, it is deformed and attached to the cavity of the mold to obtain the desired molded product. It is mainly used in the production of some daily necessities, food, and toy packaging products. Due to the low pressure during molding, the blister mold is mostly made of cast aluminum or non-metallic materials, and the structure is relatively simple.
- High-expanded polystyrene mold
It is a mold that uses expandable polystyrene (bead-shaped material composed of polystyrene and foaming agent) raw material to form foam plastic packaging materials of various required shapes. The principle is that expandable polystyrene can be molded with steam in the mold, including simple manual operation molds and hydraulic press straight-through foam plastic molds, which are mainly used to produce packaging products for industrial products. The materials used to make this type of mold include cast aluminum, stainless steel, bronze, etc.