Preproduction Plastics Inc.
Contact: Sales Manager
210 N Tellar St.
Corona, CA 92879
US-California
Phone: 909-340-9680
Fax: 909-340-1048
Gas assist injection molding is a variation of conventional injection molding that can be easily retrofitted to an existing injection press by the addition of an auxiliary gas unit. The usual injection of molten plastic is assisted by the introduction of pressurized gas (usually nitrogen) into the mold. The gas produces a bubble which pushes the plastic into the extremities of the mold creating hollow sections as the bubble propagates.
Gas assist molding offers a variety of process and design features which can help to meet application requirements. Some of the potential features and benefits are listed below:
Extend Design Guidelines
Hollow Thick Parts or Thick Sections Within Parts Can Enable:
Large ribs or flow leaders without process penalties
Higher stiffness-to-weight ratio in structured parts
Molding large cross-sections (parts consolidation)
Lower Production Costs
Short Shot Process With Hollow Sections Can Result in:
Lower clamp tonnage
Lower injection pressures
Reduced cycle time vs. solid sections
Smooth Surface Appearance Can Result in:
Improved aesthetics vs. structural foam
Reduced secondary operations
Dimensional Stability
Structural Foam Molding
The key advantages and benefits of molding parts in structural foam are as follows:
Higher processing productivity in comparison to sheet metal, wood, concrete, castings and other plastic processes. Also offers superior dimensional accuracy and repeatability when compared to fabricated or machined parts.
More strength with lower part weight thicker wall sections, up to .400 thick, give parts significantly higher strength than injection molded or other processed parts.
Size flexibility parts from 8 ounces to 35 pounds can be molded.
Lower tooling costs and longer tool life structural foam molds are typically made out of aluminum and are under far less stress and pressures, greatly reducing wear and tear.
Improved appearances structural foam lets you easily design-in many attractive features - such as ribs, bosses, hinges and curved surfaces - than most other processes.
Structural foam molding is a low-pressure injection molding process that utilizes a chemical blowing agent or nitrogen gas. Structural foam molding is an extension of the standard injection molding process, but operates under the theory of delivering a short-shot into the mold. Parts molded in structural foam are typically larger, have a much higher strength-to-weight ratio, and are virtually free of stress and sink marks. Due to the process, solid skins are formed against the walls of the mold, while the interior of the part remains foamed, which allows a typical reduction in part weight by 5-20%.
Due to the nature of structural foam molding, it leaves a swirl pattern in the surface of the part, which can require a painting operation to deliver a professional look. Structural foam parts are excellent candidates for various paint and shielding media.
TOOLING
Preproduction Plastics manufactures high quality precision tooling, specializing in quicker turnaround aluminum tooling.
Our CAD / CAM technology provides high accuracy and reduced leadtimes for our customers.
Our in-house toolroom is fully equipped with state-of-the-art CNC machines utilizing the most recent software, which allows PPI to manufacture a wide range of molds. PPI also provides the best mold maintenance program, ensuring a long life to any mold.
Software & Hardware
Mold Flow® software
Cadkey® CAD interface software
MasterCAM® CAM software
One Pentium IV 1500mhz and three Pentium III computers
One Hewlett Packard Design Jet 2500 CP
CNC Machining Centers
Two Leblond Makino MC-100
Two Fadal VMC 40-20
Two Fadal VMC 5XT
One Fadal VMC 10XT
Two Fadal VMC 10
EDM (Electrical Discharge Machines)
Two Hansvedt Master machines
Additional Tools
One Victor Engine Lathe
One Willis Radial Arm Drill
One Haiq Surface Grinder
One Master Tool Grinder
One Miller Arc Welder
One 6 ton Forklift
