1.Different Production Principle
Both vacuum forming and injection molding are plastic processing processes, but they are made on different principles.
The thick vacuum forming plastic products are made of thermoplastic sheet as raw material. After the plastic sheet is heated, the vacuum pressure is formed between the sheet and the mold, so that the sheet will be adsorbed on the surface of the mold. They are sealed around and the vacuum inside is evacuated to make the sheet stick completely to the mold, which form the same shape as the mold. Finally the sheet is cooled by a fan and then it can be released.
Injection molding refers to that the sheet is heated by the injection molding machine to reach the degree that it can melt into liquid, then the liquid will be injected into the closed mold cavity with high pressure. After cooling and shaping, plastic products can be produced once the mold is opened.
2.Different Types of Application
Thick vacuum forming plastic products are mainly used for machine shells, large appliances, electric car cladding, logistics pallets, large toys, lighting covers, advertising light boxes, display shelves and sanitary ware and other major industries.
Injection molded products are commonly used in cell phone cases, computer cases, plastic cups, mouse boxes, hardware accessories, etc.
3.Different production cycles
Thick vacuum forming plastic products are a heating and flexible production model that can be used to mold multiple products in a single run.
On the other hand, injection molding has long production cycles and is produced by pressing multiple products from a single mold and do not require individual splits to form the product directly.
4.Comparison of Advantages and Disadvantages
Thick Vacuum Forming Plastic Product | Injection-molded Product | |
Advantage | Lower mold cost than injection moldingShort production cycleSuitable for smaller batchesLightweightCorrosion-resistant | Fast production speedHigh efficiencyAutomated operation,Wide variety of designAccurate dimensionSuitable for mass production |
Disadvantage | Only one side can be vacuum formedMore accurate dimensions of the product surface in direct contact with the mold.Higher costSomewhat uneven wall thickness | High cost of molding equipmentVulnerable proficiencyThe temperature of the injection mold is high, so it needs a long cooling time after blowing in the mold, which makes the whole molding cycle of the product longer.High demand for operators’ skills |