The 5 most common plastic injection molding processes
1 Injection Molding
The principle of injection molding is to add granular or powdered raw materials into the hopper of injection machine, and the raw materials are heated and melted into a liquid state, then pushed by the screw or piston of the injection machine, enter the mold cavity through the nozzle and the pouring system of the mold, and harden and set in the mold cavity. The elements affecting the quality of injection molding: injection pressure, injection time, injection temperature.
Process Technology features.
1, short molding cycle, high production efficiency, easy to automate
2, can mold complex shape, precise size, with metal or non-metal insert plastic parts
3, Stable product quality
4, wide range of applications.
1, Injection molding equipment price is high
2, Complex structure of injection mold
3, high production costs, long production cycle, not suitable for single small batch production of plastic parts
In industrial products, injection molded products include kitchenware (garbage cans, bowls, buckets, jugs, tableware, and various containers), housings for electrical equipment (blowers, vacuum cleaners, food mixers, etc.), toys and games, various parts for the automotive industry, parts for many other products, etc.
2 Insert Molding
Insert molding application
Insert molding is a molding process in which a mold is filled with pre-prepared inserts of different materials and then injected with resin, and the molten materials are joined with the inserts and cured to make an integrated product.
Process Technoloy characteristics
1, Multiple inserts are combined in advance, making the post-engineering of product unit combination more reasonable.
2, The combination of resin’s ease of molding, bending and metal’s rigidity, strength and heat resistance can be supplemented to make complex and delicate metal-plastic integrated products.
3, Particularly, the combination of resin’s insulation and metal’s electrical conductivity can make molded products that can meet the basic functions of electrical products.
4, For rigid molded products and rubber gaskets, the injection molding of integrated products on the substrate eliminates the complicated work of arranging seals and makes it easier to automate the post-process assembly.
3 Double color injection
Double color injection example
Double-color injection molding: It is a molding method that injects two different colors of plastic into the same mold. It can make the plastic appear in two different colors and can make the plastic parts present regular patterns or irregular cloud-like patterns to improve the usability and beauty of the plastic parts.
Process Technology characteristics.
1, The core material can use low viscosity material to reduce the injection pressure.
2, From the consideration of environmental protection, the core material can use the recycled secondary material.
3, cording to the different characteristics of use, such as the use of soft material for thick finished skin material, hard material for core material or core material can be used to reduce the weight of foam plastic.
4, an use lower quality core material to reduce costs.
5, skin material or core material can use the expensive and with special surface properties. Such as anti-electromagnetic interference, high electrical conductivity, and other materials to increase product performance.
6、Appropriate skin material and core material can reduce the residual stress of molded products, increase the mechanical strength or product surface properties.
4 Microcellular Foam Injection Molding(MFIM)
Microcellular foam injection molding process: It is an innovative precision Injection molding technology, which relies on the expansion of pores to fill the product, and completes the molding of the part under a low and average pressure. The process of microcellular foam molding can be divided into three stages: first, the supercritical fluid (carbon dioxide or nitrogen) is dissolved into the hot melt glue to form a single-phase solution; then the mold cavity with lower temperature and pressure is injected through a switch-type nozzle, which triggers the instability of molecules due to the lower temperature and pressure to form a large number of bubble nuclei in the product, and these bubble nuclei gradually grow to generate tiny holes.
Process Technology features
1, Precision injection molding.
2, Breakthrough the many limitations of traditional injection molding, can significantly reduce the weight of the parts, shorten the molding cycle.
3, greatly improve the warpage deformation and dimensional stability of the parts.
Automobile instrument panels, door panels, air conditioning ducts, etc.
5 Nano Molding Technology（NMT）
NMT (Nano Molding Technology): It is a method of combining metal and plastic with nanotechnology, firstly, the metal surface is treated with nanosize, and then the plastic is directly injected and molded on the metal surface, so that the metal and plastic can be formed as one. Nanomolding technology according to the location of the plastic is divided into two types of processes.
1, plastic for the non-appearance of the surface of the one-piece molding
2, plastic for the appearance of the surface of the integrated molding
Process Technology features：
1, the product has a metallic appearance and texture.
2, the design of the product mechanism is simplified, so that the product is lighter, thinner, shorter, smaller, and more cost-effective than the CNC processing method.
3, reduce production costs and high bonding strength, and significantly reduce the use of related consumables
Applicable metal and resin materials.
1, Aluminum, magnesium, copper, stainless steel, titanium, iron, galvanized sheet, brass.
2, aluminum alloy is more adaptable, including 1000 to 7000 series.
3, resins including PPS, PBT, PA6, PA66, PPA.
4, PPS has a particularly strong bonding strength (3000N / c㎡).
Cell phone casing, laptop casing, etc.
Injection molding is widely used in various industries and can achieve seamless and precise mass production of parts in a short period of time. Prolean Tech offers injection molding services for dozens of materials, including plastics and elastomers. Simply upload your CAD file for a quick, free quote and consultation on related services.
Post time: Apr-02-2022