EVCO Plastics has employed gas assist molding technology for plastic injection molding in a wide range of applications for over 20 years, providing OEM’s with numerous advantages for custom plastic injection molded plastic parts and products. Gas assist injection molded plastics are a great option for companies looking to reduce time and cost without sacrificing quality or design options.
Gas assist molding is a low pressure plastic injection molding process where pressurized nitrogen gas is injected into the mold, pushing the plastic into the mold extremities, while hollowing out thicker sections in the part.
In the gas assist molding process, the plastic material is melted and injected into the mold cavities via the conventional plastic injection molding process. Plastic material in contact with the mold walls begins to solidify first. As this happens, nitrogen gas is injected into the mold through strategically designed and placed gas channels, providing pressure that pushes the plastic material into the mold extremities. Once the plastic cures, the nitrogen is vented and the gas assist injection molded plastic parts are removed from the mold. Gas assist injection molding process animation.
Advantages of Gas Assist Molding
Less plastic material needed (material savings)
Reduced part weight (in some cases up to 40%)
Decreased cycle time
Increased part strength and rigidity
Reduced warpage and distortion
Improved part appearance (eliminates sink marks and surface blemishes)
Reinforces ribbed parts
Increased design options for complex parts, reducing multiple part assemblies, and metal to plastic conversions
Enables use of smaller plastic injection molding presses