Why Gas-Assisted Injection Molding Simulation?
Gas-assisted injection molding (GAIM) is a process where an inert gas is injected into an injection molded part during the filling stage. The process utilizes compressed gas as the “packing medium”, which provides mechanical strength and dimensional stability for thick molded parts, and eliminates warpage and sink marks of products caused by pressure variation and residual stress. In GAIM, plastic products are molded under lower injection pressure with less material, which benefits companies on energy and weight savings.
For GAIM, gas control becomes the main challenge due to the distinct properties and resistances of gas and plastic flows. Moldex3D GAIM provides tools to simulate gas injected into cavities through either melt entrances or any specific gas entrances. The 3D model enables users to visualize gas penetration inside the mold cavity and further to optimize the part/mold design and process settings.
(a) GAIM with short shot method |
(b) GAIM with overflow region valve gate control |
Challenges
- Determine the gas entrance number and location
- Optimize gas process condition to control the skin thickness and penetration field
- Verify gas channel designs, such as size or placement
- Predict potential corner effect and blow through based on skin thickness distribution
What Can Moldex3D Do?
- Visualize gas penetration and hollowed core ratio over time in cavities in any cross-section.
- Determine proper parameters including gas enter/delay time, gas injection points, overflow regions and more
- Access to a variety of gas assisted injection molding methods such as short shot, full shot, and overflow processes
- The complete cycle simulation allows users to obtain in-depth knowledge in each stage and detect defects such as weld lines, flow marks, and any forms of dimensional instabilities
A GAIM mold from (a) experiment and (b) simulation result
Comparison of simulation and experiments in hollowed-core ratio along gas front
Applicable Industries
- Electronics
- Automotive
- Medical
- Consumer Product
Applicable Moldex3D Package
- Moldex3D Professional Package
- Moldex3D Advanced Package