Do you know about vacuum forming? If not, that's okay. Join us as we explore the vacuum forming process with Dongguan Vacuum Forming Factory.
One, the vacuum forming principle utilizes a vacuum forming machine. By applying power to the heating elements on the vacuum forming mold, the PVC vacuum forming cover and the vacuum forming card are heated, achieving melting in a short time. Simultaneously, under high pressure, the pressure is maintained, and cooling is applied to complete the vacuum forming process. During this working process, heating and pressure are carried out simultaneously.
The vacuum forming machine operates in two types: pneumatic and electric, with the pneumatic type being commonly used. Here's an explanation of the pneumatic type's working principle: The pneumatic vacuum forming machine utilizes compressed air and cylinder transmission, offering fast operation. By adjusting the input air pressure and flow rate, the speed and pressure of the plate's rise and fall can be controlled, making maintenance and care simple and convenient. Transparent PS performance parameters: Density: 1.04 g/cm³, Tensile Strength: Longitudinal ≥26MPa, Lateral ≥24MPa, Impact Strength (without切口): 18KJ/m
Plaster molds, rubber molds, and gypsum molds are primarily made using yellow vacuum-formed gypsum powder. If drawings are provided, the gypsum material is milled and hand-finished according to the drawing specifications and requirements. If a physical sample is provided, the outline of the mold is first handcrafted from clay, vacuum formed into a vacuum cover, and then cast into a gypsum mold, with further modifications made to the mold. The process typically takes 2-4 days. Gypsum mold making is easy and quick, beneficial for product packaging modifications, and cost-effective, though it has lower durability and is more prone to damage after prolonged use, resulting in products with lower transparency. Mainly suitable for initial board confirmation and products with low transparency requirements for outer packaging.
Defects in Blown Molding Products
Scratches: Excessive lines or protrusions (not present on the mold) can occur during the vacuum forming production process. These require reworking the mold (by reducing height and increasing smoothness) and adding an additional pressure mold (referred to as the upper mold) to address. While large scratches are considered defective, in the realm of component turnover trays, they should be deemed acceptable as long as the lines are neatly arranged and do not affect the functionality. Scratches are also known as: pull lines, draw strings, etc.
Scratches: Any indentation marks on the vacuum-formed products, particularly on transparent blister packs, are considered defects. If the scratches are too long or too large, the blister pack is deemed substandard.
Jingdian: During the production of vacuum-formed sheet materials, a transparent defect is caused by fine dust in the air falling onto the heated plastic material. This is particularly noticeable in the production of transparent vacuum-formed sheet materials, where such defects, when large and numerous, are deemed substandard products.
Bubble: During the process of producing vacuum-formed plastic sheets, the presence of air within the heated plastic material leads to bubbles in the finished sheets. Particularly in the production of clear vacuum-formed plastic sheets, excessive and large bubbles are considered defective products.
