What is plastic mould?
Types of plastic molds
Plastic molds are tools that are matched with plastic molding machines in the plastic processing industry to give plastic products a complete configuration and precise dimensions.
Due to the wide variety of plastics 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.
What is plastic mould
A combined plastic mold for compression molding, extrusion molding, injection molding, blow molding and low foam molding. It mainly includes a concave mold with a variable cavity composed of a female mold combined substrate. A female mold component and a female mold combined card board, a convex mold combined substrate, a male mold component, a male mold combined card board, and a cavity cutting component A punch with a variable core composed of a side-cut composite board.
Coordinated changes of mold convex, concave mold and auxiliary molding system. Series of plastic parts of different shapes and sizes can be processed. In the plastic processing industry, it is matched with plastic molding machines to give plastic products a complete configuration and precise size tools.
Due to the wide variety of plastics 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.
Injection mould overview
The mold is clamped on the injection molding machine, and the molten plastic is injected into the molding cavity. And it is cooled and shaped in the cavity, and then the upper and lower molds are separated.
The product is ejected from the mold cavity and out of the mold via the ejection system. Finally, the mold is closed for the next injection, and the entire injection process is carried out cyclically.
Types of plastic mould
Plastic injection mold
It is mainly a molding die that is most commonly used in the production of thermoplastic parts. The processing equipment corresponding to the plastic injection mold is the plastic injection molding machine.
The plastic is heated and melted in the heating barrel at the bottom of the injection machine, and then driven by the screw or plunger of the injection machine, it enters the mold cavity through the injection machine nozzle and the pouring system of the mold. The plastic is cooled, hardened, and molded, and then demolded to obtain a product.
Its structure is usually composed of molding parts, pouring system, guide parts, push-out mechanism, temperature control system, exhaust system, support parts and other parts. Manufacturing materials usually use plastic mold steel modules, and the 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. The plastic products produced by the injection molding process are very extensive. From daily necessities to all kinds of complex machinery, electrical appliances, vehicle parts, etc., they are all molded by injection molds. It is the most widely used processing method in the production of plastic products.
Plastic Compression Mold
It includes two structural mold types: compression molding and injection molding. They are a type of molds mainly used to form thermosetting plastics, and their corresponding equipment is a pressure forming machine.
The compression molding method is based on the characteristics of the plastic. Heat the mold to the molding temperature (generally 103°-108°). Then the measured compression powder is put into the mold cavity and the feeding chamber, and the mold is closed. The plastic is softened and viscous under the action of high heat and high pressure. After a certain period of time, it will be solidified and shaped into 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, and the plastic is preheated in the feeding chamber and is in a viscous flow state. Adjust and squeeze into the mold cavity under pressure to harden and shape.
Compression molds are also used to mold some special thermoplastics such as hard-to-melt thermoplastics (such as polyvinyl fluoride) blanks (cold forming). Resin lenses with high optical performance, slightly foamed nitrocellulose car steering wheels, etc.
The compression mold is mainly composed of a cavity, a feeding cavity, a guiding mechanism, an ejecting part, a heating system, etc. Injection molds are widely used for packaging electrical components. The material used in the manufacture of compression moulds is basically the same as that of injection moulds.
Plastic extrusion mould
A type of mold used to mold and produce continuous-shaped plastic products is also called extrusion molding. It is widely used in the processing of pipes, rods, monofilaments, plates, films, wire and cable coatings, profiled materials, etc.
The corresponding production equipment is a plastic extruder. The principle is that the solid plastic is melted and plasticized under the conditions of heating and the screw of the extruder to rotate and pressurize, and a continuous plastic product with the same cross-section and the shape of the die is made through a die of a specific shape.
Its manufacturing materials mainly include carbon structural steel, alloy tools, etc. Some extrusion dies will also be inlaid with wear-resistant materials. Such as diamond on the parts that need to be wear-resistant. The extrusion process is usually only suitable for the production of thermoplastic products. And its structure is obviously different from injection molds and compression molds.
Plastic blow mould
It is a mold used to form hollow plastic container products (such as beverage bottles, daily chemical products and other packaging containers).
The forms of blow molding are mainly extrusion blow molding hollow molding, injection blow molding hollow molding, injection stretch blow molding hollow molding, multi-layer blow molding hollow molding, and sheet blow molding hollow molding.
The corresponding equipment for 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 mold that uses plastic plates and sheets as raw materials to form some simpler plastic products.
The principle is to use the vacuuming method or compressed air molding method to deform the plastic plates or sheets fixed on the concave mold or the convex mold under the condition of heating and softening, and then stick to the cavity of the mold to obtain the desired molded product.
Mainly used in the production of packaging products such as daily necessities, food and toys. Due to the low pressure during forming. The blister mold is made of cast aluminum or non-metallic materials, and the structure is relatively simple.
High-expanded polystyrene molding die
It is the application of expandable polystyrene (beads composed of polystyrene and foaming agent). The raw material is used to form a mold of foamed plastic packaging materials of various desired shapes.
The principle is that expandable polystyrene can be steam-formed in the mold. Including simple manual operation molds and hydraulic straight-through foam plastic molds, mainly used to produce industrial packaging products. The materials used to make this kind of molds are cast aluminum, stainless steel, bronze and so on.