When a company requires the formation of a hollow shape, such as a plastic bottle, it is considering hiring a company specializing in blow molding. This process is capable of taking plastic material, creating an appropriate mold design and producing bottles or bottle-type shapes. When the shape, size or conformation is unusual, it becomes necessary to consider custom blow molding.
Materials
Selection of the material used for blow molding differs according to the intended application. Factors influencing the choice for a particular project will be
• Physical properties
• Environment
• Cost
When it comes to the blow molding of bottles, the most common choice is Polyethylene terephthalate (PET). Other options for both blow and custom blow molding are:
• Polyethylene
• High-density polyethylene (HDPE)
• Polypropylene
• Nylon
Companies use these materials to produce their products using any of three common standard and custom blow molding methods.
Processing Methods
Whether the intent is to create a hollow or balloon shape, companies look at one of three possible methods. They are similar but do have certain differences.
• Extrusion Blow Molding (EBM): During this process, the operator heats the selected plastic to its melting point. At this point, s/he forces it to enter into a parison (hollow tube). While cooling down upon placement in a metal tube, a device blows air into the parison. This results creation of the preferred shape.
• Injection Blow Molding: This is more common for the production of medical components. The process is similar but involves injecting the material into the cavity.
• Injection Stretch: This is similar to the injection process. This option is the most versatile of the 3 methods.
Custom Blow Molding
Plastic is the material of choice for many components and products. When it comes to creating hollow shapes, the first choice is standard or custom blow molding. By choosing the right plastics and employing the right process, manufacturers are guaranteed the hollow shapes and bottle-forms they require to contain or display their product.