Gas-Assisted Injection Molding
Eliminate sink marks and reduce weight with JUCHENG’s gas assisted injection molding services. We provide advanced nitrogen gas assist molding to create hollow plastic part manufacturing solutions for thick-walled components and large structural frames.
The Thick-Wall Molding Challenge
Standard injection molding cannot handle thick, bulky cross-sections. As a thick mass of plastic cools, it shrinks unevenly, pulling the surface inward and creating unacceptable cosmetic defects.
Standard Molding (The Problem)
When attempting to mold thick parts (like handles or thick bezels) traditionally, the outer skin cools first while the molten core continues to shrink. This results in severe sink marks, internal voids, warping, and extended cycle times that destroy production efficiency.
Gas-Assist Molding (The Solution)
We inject a precisely measured “short shot” of polymer into the mold. Immediately after, highly pressurized inert Nitrogen gas is injected into the core of the melt. The gas pushes the molten plastic outward against the cavity walls, hollowing the part and packing it uniformly from the inside out.
Precision Tooling for Perfect Gas Channels
Gas takes the path of least resistance. If your mold is not designed and machined with absolute precision, the gas will blow through the thin walls or fail to core out the thick sections, destroying the part.
This is where Jucheng’s Tooling Mastery comes in:
- Strategic Gas Pin Placement: Our engineers use advanced Moldflow analysis to precisely locate gas injection pins or nozzles for optimal channel routing.
- 5-Axis CNC Accuracy: We utilize our 25+ advanced 5-axis CNC machines to cut complex, continuous thick-to-thin transitions in the mold steel with micron-level accuracy.
- Perfect Sealing: Gas-assist molds require exceptional shut-off tolerances to prevent high-pressure nitrogen leaks. We guarantee zero-flash molds.
Why Choose Gas-Assisted Molding?
Our gas assisted injection molding services are the key to eliminating sink marks with nitrogen gas. By utilizing internal gas pressure molding, we deliver thick-walled molding solutions that are 40% lighter, making it ideal for gas-assist for large panels and handles.
Flawless Class-A Surfaces
The internal gas pressure packs the plastic firmly against the mold walls as it cools, completely eliminating sink marks on thick sections.
Up to 40% Weight Reduction
Hollowing out thick sections significantly reduces the volume of resin used, leading to lighter parts and substantial material cost savings.
Increased Structural Rigidity
By designing hollow tubular cross-sections (like pipes), parts achieve a much higher strength-to-weight ratio and torsional stiffness.
Lower Clamping Force
Internal gas pressure replaces massive machine packing pressure. Large parts can be run on smaller presses (from our 35+ fleet), lowering part costs.
DfM: Designing for Gas Channels
Designing for gas-assist requires a shift in engineering thinking. You must intentionally design the "gas channels"—the thick sections where the nitrogen will flow.
Continuous Channel Design
Gas channels should be continuous and form a complete network. Avoid dead ends or sharp 90-degree turns where the gas can become trapped or blow out the side wall.
Smooth Transitions
The transition from thin walls to the thick gas channel must be gradual. Abrupt changes in wall thickness will cause flow hesitation and uneven hollowing.
Ribs as Gas Channels
Thick structural ribs at the base of a part can be designed as gas channels. The gas hollows the base of the rib, eliminating the sink mark on the visible side of the part.
Optimize your hollow structure for maximum weight reduction.
Evaluate My Geometry →Hollowing Out Weight Across Industries
We produce high-strength, lightweight, and cosmetically perfect components for the world's leading brands.
Automotive Components
IATF 16949 certified production of extremely rigid, lightweight exterior door handles, large interior dashboard fascias, and structural seat frames with zero sink marks.
Consumer Appliances
Thick, ergonomic handles for refrigerators and ovens, and large, rigid chassis components for televisions and monitors requiring perfect Class-A glossy finishes.
Industrial & Medical
Large, bulky covers and thick-walled housings for medical imaging machines and industrial equipment, significantly reducing part weight and material costs.
Ready to Eliminate Sink Marks and Reduce Weight?
Our tooling engineers are experts in gas channel design and mold flow analysis. Upload your 3D CAD files today for a free DFM report and a comprehensive production quote within 24 hours.
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