Goldwin has over 23 years of experience in high-precision mold making and plastic injection. One of our key capabilities is thin wall injection molding, a process designed for producing lightweight, intricate plastic parts with exceptional precision and efficiency.

What Is Thin Wall Injection Molding?

Thin wall injection molding typically refers to the production of plastic parts with walls less than 1mm thick. More specifically, when the flow length-to-thickness ratio (L/t) exceeds 150, the process is categorized as thin wall molding. This method is especially effective for applications requiring reduced material use without compromising strength or structure.

Benefits of Thin Wall Molding

Reducing wall thickness minimizes plastic consumption, which can represent 50–80% of total production costs. The growing demand for compact and lightweight electronics drives the need for thinner, more precise plastic components.

Critical Process Requirements

• High-Speed Injection: Rapid filling prevents premature solidification of material.
• Low Inertia & High Acceleration: Essential for quick response and uniform flow.
• High Rigidity Systems: Robust structures ensure consistent molding accuracy.
• Servo Valves & Closed-Loop Control: Enable precise, real-time adjustments for superior product consistency.

Cycle Efficiency & Machine Design

Short molding cycles (often under 4 seconds) are achieved through fast mold movements and efficient part ejection. A high-rigidity mold structure ensures dimensional stability across repeated cycles.

Plasticizing Performance

Thin wall molding requires high melt flow and efficient plasticizing. Longer screws (L/D 24–25), high screw speeds, and pneumatic nozzles help maintain throughput. High-MI PP is a preferred material.

Mold Engineering & Venting

• Thick mold bases reduce deformation.
• Exhaust systems—vent slots, breathable steel, or vacuum—prevent air traps.
• Multi-cavity molds demand high uniformity and fast demolding mechanisms.

Material Selection

High-flow materials such as PP, PE, PS, ABS, and PC are commonly used. These materials are ideal for rapid filling in thin wall designs with flow ratios exceeding 200.

Gate & Vent Optimization

• Balanced gate design ensures consistent flow.
• Exhaust features like vents and vacuum systems reduce molding resistance.
• Thicker runners and gates compensate for fast cooling cycles.

Machine Capabilities

• Injection pressure ≥ 200 MPa
• Clamping force of 5–8 tons/in²
• Injection speed up to 2200 mm/s; response time ≤ 11 ms

Advanced machines (e.g., screw-plunger, nitrogen-assisted) deliver the precision and speed required for optimal thin wall molding.

Control and Monitoring

Thin wall molding requires simultaneous, independent control of pressure and speed. High-resolution microcontrollers help prevent defects like burn marks or air entrapment by maintaining optimal temperature, shear rate, and ventilation.

Conclusion

Thin wall injection molding supports today’s manufacturing demands for cost-effective, high-performance parts. By aligning part design, mold engineering, machine performance, and precise process control, manufacturers like Goldwin ensure top-tier quality, repeatability, and efficiency across all thin wall applications.

Looking to enhance your manufacturing with expert thin wall injection molding solutions?
📩 Contact us today to discuss your project and discover how we can help you achieve precision, efficiency, and superior quality.