Mould is an important process equipment of modern indus […]
Mould is an important process equipment of modern industry and an indispensable part in the production of many industrial products. After China's accession to the WTO, its ability to attract foreign investment has been increasing year by year, and its status as a world product manufacturing factory has become more prominent, with more and more imports of various industrial product molds.
The types of molds are usually classified according to the processing objects and processes. From the perspective of the industry, there are mainly plastic molds, rubber molds, metal cold punching molds, metal cold extrusion molds and hot extrusion molds, and metal drawing molds. , Powder metallurgy molds, metal die-casting molds, metal precision casting molds, glass molds, glass steel molds, etc.
The following is only how to classify and introduce the different types of molds used in the molding and processing of common imported plastic products.
The common molding methods of plastics are generally divided into two categories: melt molding and solid phase molding: Melt molding is a method of heating plastics above the melting point and making them in a molten state for molding processing. It belongs to the molding process of this molding method. There are mainly injection molding, compression molding (shrink) molding, extrusion molding, etc.; solid phase molding refers to a type of molding method in which plastics remain solid below the melting temperature, such as vacuum molding, compressed air molding and Blow molding, etc. In addition, there are liquid molding methods, such as casting molding, slush molding, and dip molding.
According to the different molding methods mentioned above, the types of plastic processing molds corresponding to different process requirements can be divided, mainly including injection molding molds, extrusion molding molds, compression molding molds, blow molding molds, blister molding molds, and high-foaming polystyrene Ethylene molding die, etc.
Plastic injection (plastic) mold
It is mainly a molding mold that is commonly used in the production of thermoplastic plastic products. The corresponding processing equipment of the plastic injection molding mold is a plastic injection molding machine. Driven by the screw or plunger, it enters the mold cavity through the nozzle of the injection machine and the pouring system of the mold, the plastic is cooled and hardened to form, and the product is demolded. 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 wide. From daily necessities to various complex machinery, electrical appliances, and transportation parts, they are all molded by injection molds. It is a widely used processing method in the production of plastic products.
Plastic Compression Mold
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, heating the mold to the molding temperature (usually 103 ℃-180 ℃), and then put the measured compression powder into the mold cavity and the feeding chamber, close the mold, and the plastic acts under high heat and high pressure. The bottom is softened and viscous, and after a certain period of time, it is solidified and shaped into the desired product shape. The difference between injection molding and compression molding is that it is equipped with a separate feeding chamber. The mold is closed before molding. The plastic is preheated in the feeding chamber and is in a viscous flow state. It is squeezed into the mold cavity at high speed under pressure to harden and form. Compression molds are also used to mold some special thermoplastics, such as hard-to-melt thermoplastics (such as polytetrafluoroethylene) 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 molds is basically the same as that of injection molds.
Plastic Extrusion Mould
is a type of mold used to mold and produce continuous-shaped plastic products, also called extrusion molding heads, which are 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 rotation and pressure of the extruder, and the cross-section is the same as the shape of the die through a specific shape of the die. Continuous plastic products. Its manufacturing materials mainly include carbon structural steel, alloy tool steel, etc. Some extrusion dies will also be inlaid with wear-resistant materials such as diamond on the parts that need to be wear-resistant. Extrusion processing technology 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 kind of mold used to form plastic container hollow products (such as beverage bottles, daily chemical products and other packaging containers). The forms of blow molding are mainly extrusion blow molding hollow molding and injection blow molding hollow molding according to the process principle. , Injection stretch blow molding hollow molding (commonly known as "injection stretch blow"), multilayer blow molding hollow molding, sheet blow molding hollow molding, etc. 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 steel.
plastic blister mold
It is a kind of mold that uses plastic plates and sheets as raw materials to form some simpler plastic products. The principle is to use the vacuum molding method or compressed air molding method to make the plastic plates and sheets fixed on the concave mold or the convex mold. Under the condition of heating and softening, it is deformed and pasted on the cavity of the mold to obtain the desired molded product, which is mainly used in the production of some daily necessities, food, and toy packaging products. The blister mold is made of cast aluminum or non-metallic materials because of the low pressure during molding, and the structure is relatively simple.
high-expanded polystyrene molding die
is a mold that uses expandable polystyrene (bead-like particles composed of polystyrene and foaming agent) raw materials to form various desired shapes of foam packaging materials. The principle is that the expandable polystyrene is steamed into the mold, including two types of simple manual molds and hydraulic straight-through foam plastic molds, which are mainly used to produce industrial packaging products. The materials used to make this type of mold include cast aluminum, stainless steel, bronze and so on.