What Is Vacuum Forming?
Vacuum forming is a manufacturing method used to shape plastic materials. During the LED Advertising Light Vacuum Forming process, a sheet of plastic is heated and then pulled around a single mold using suction.
Vacuum forming is used for a wide range of manufacturing applications, ranging from small custom parts produced on desktop devices to large parts manufactured on automated industrial machinery.
What are the Differences Between Vacuum Forming, Thermoforming, and Pressure Forming?
Thermoforming is a manufacturing process where a sheet of plastic is heated to become pliable, then shaped or contoured using a mold, and trimmed to create a final part or product. Vacuum forming and pressure forming are both different types of thermoforming processes. The main difference between pressure forming and vacuum forming is the number of molds that are used.
Plastic Trays Vacuum Forming is the simplest type of plastic thermoforming, that uses one mold and vacuum pressure to obtain the desired part geometry. It is ideal for parts that only need to be precisely formed on one side, such as contoured packaging for food or electronics.
There are two basic types of molds—male or positive (which are convex) and female or negative, which are concave. With male molds, the sheet of plastic is placed over the mold to contour the inside dimensions of the plastic part. With female molds, the thermoplastic sheet is placed inside the mold to form the outer dimensions of the part precisely.
In pressure forming, a heated sheet of plastic is pressed (hence the name) between two molds instead of being pulled into place around a single mold using suction. Pressure forming is ideal for manufacturing plastic parts or pieces that need to be more precisely shaped on both sides and/or require a deeper draw (they need to extend farther/deeper into a mold), such as appliance casings that need to look aesthetically pleasing on the exterior and snap into place or fit a precise size on the interior side.
How Does Vacuum Forming Work?
The step-by-step Automotive Plastic Parts Vacuum Forming process works as follows:
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Clamp: A sheet of plastic is placed in an open frame and clamped into place.
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Heat: The plastic sheet is softened using a heat source until it reaches the appropriate forming temperature and becomes pliable.
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Vacuum: The framework containing the heated, pliable sheet of plastic is lowered over a mold and pulled into place via a vacuum on the other side of the mold. Female (or convex) molds need to have tiny holes drilled into crevices so that the vacuum can effectively pull the thermoplastic sheet into the appropriate form.
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Cool: Once the plastic has been formed around/into the mold, it needs to cool. For larger pieces, fans and/or cool mist are sometimes used to speed up this step in the production cycle.
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Release: After the plastic has cooled, it can be removed from the mold and released from the framework.
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Trim: The completed part will need to be cut out of the excess material, and edges may need to be trimmed, sanded, or smoothed.
Vacuum forming is a relatively quick process with the heating and vacuuming steps typically taking only a few minutes. However, depending on the size and intricacy of the parts being manufactured, cooling, trimming, and creating molds can take considerably longer.
Industrial
Manufacturers also use Thermoforming Machine and Equipment Shell to produce many industrial crates and contoured containers for machinery. Vacuum forming is a great manufacturing process for parts primarily used outside or ones that may come in contact with a heat source because industrial manufacturers can use a variety of flame-retardant and UV-resistant materials. For example, fire-retardant UL 94 V-0 polyvinyl chloride (PVC) and UV filtering acrylic (PMMA) can both be vacuum formed.
Medical
Medical Equipment Vacuum Forming Cases and components that need to be antimicrobial or have resistance to contaminants are often manufactured through vacuum forming. This includes medical packaging, the pharmaceutical trays pills are packaged in, components of hospital beds, and MRI and CT machine exterior pieces.
