Gas Assisted Mold
Gas-assist injection molding is a process that produces large plastic parts with complex designs and superb cosmetic and surface finishes. The process is especially ideal for large handles, equipment covers, doors, bezels, cabinets and skins. Gas-assist injection molding is a low-pressure process that requires the injection of pressurized nitrogen gas into the interior of a mold. The gas flows through strategically placed gas channels to displace the material in the thick areas of the part by forming hollow sections. The pressurized gas pushes the molten resin tight against the cavity walls until the part solidifies, and the constant, evenly transmitted gas pressure keeps the part from shrinking while also reducing surface blemishes, sink marks, and internal stresses. This process significantly reduces material usage while producing a part with superior structure and aesthetics.
Along with the substantial reduction of material cost, additional savings are achieved through use of the gas assist process. Since it requires typically one-third the clamping forces of conventional injection molding, it can be performed more economically on smaller presses and with faster cycle times. Reduced in-mold pressure also allows the use of less expensive steel or aluminum tooling while subjecting it to less wear-and-tear. Parts also weigh considerably less, which results in reduced freight expense and improved material handling efficiencies.
Cost saving is not the only benefit. This technology offers many design and performance advantages over other large part molding processes. Long shapes and multiple parts with complex designs and differing wall thickness can be molded as a single part and with tighter tolerances. In addition, parts exhibit improved dimensional stability, better quality surfaces, and require minimal or no secondary operations.
Gas-assist injection molding is an attractive option for producing a better quality alternative to an existing large metal part. Customers achieve tremendous cost savings and performance benefits by eliminating expensive, heavy, corrosion-prone parts such as covers, enclosures, access doors, and panels. Another attractive conversion opportunity is the replacement of existing thermoformed, vacuum formed, or pressure formed parts. Formed parts require labor-intensive, expensive secondary operations, and at an optimal quantity target, the cost savings associated with gas assist justifies the investment in tooling to convert to an injection molded part.
Through early involvement in the engineering and design process, POWSTAR can provide you with a competitive advantage through the use of gas-assist plastic injection molding. Contact us today to learn more.