Rapid Prototyping and Mass Production Solutions for Two-Color Injection Molded Parts

I. Rapid Prototyping: Accelerating Product Validation

The core of rapid prototyping is to verify design feasibility efficiently, laying a precise foundation for mass production through 

the following key steps:

1. Fast-Response Mold Design

Select mold types based on prototyping needs to balance speed and precision:

Concept verification (≤30 units): Use SLM metal 3D-printed cores with standardized mold frames, completing assembly within 

48 hours to test material bonding and basic formability.

Small-batch trial production (100-500 units): Adopt insert-type pre-production molds with reusable frames; only CNC-machined

 inserts need replacement (3-5 day delivery), simulating mass production parameters (holding pressure, cooling) to reduce subsequent 

adjustments.

Design focuses on optimizing bonding interfaces, such as adding 0.1-0.2mm steps to enhance mechanical locking and reserving 

vents to prevent air bubbles.

2. Material Compatibility System

Predefined material combinations and testing standards streamline validation:

Key tests: Thermal matching (DSC-verified Tg difference ≤20℃) and bonding strength (≥8N/cm per ASTM D903) to ensure reliability 

for medical and automotive applications.

Preset combinations: PC+TPE (consumer electronics), PP+TPE (automotive interiors), PEEK+silicone (medical devices), with 

ready-to-use parameters to minimize trial-and-error.

3. Rapid Process Parameter Tuning

Leverage simulation tools to reduce trial runs and lock in parameters:

Mold flow simulation: Predict filling sequences and gate positions via Moldflow; optimize second-shot injection speed (30-50mm/s) 

for curved products to avoid weld lines or warpage.

Critical parameters: First-shot holding pressure 80-100bar, cooling to 50-60℃, 2-5s interval before second shot. Minor deviations are 

corrected via ±2℃ mold temperature or ±5bar pressure adjustments.

4. Quality Validation Standards

Verify against mass production requirements:

Appearance: Check boundary clarity, flow marks, and color consistency under standard lighting.

Dimensions: Focus on bonding area tolerances (±0.05mm).

Performance: Conduct 50-cycle alcohol rub tests and -20℃ low-temperature impact tests.

Approved data is compiled into a "prototyping parameter package" for direct use in mass production.

II. Mass Production: Stable and Efficient Scale Delivery

Mass production balances quality stability and efficiency through systematic solutions to achieve low-cost, high-reliability output:

1. Precision Equipment Configuration

Select equipment based on production volume and product complexity:

High-volume standard products (e.g., phone buttons, ≥100,000 units/day): Use rotary two-color machines with servo-driven 

turntables (0.02mm positioning accuracy) to ensure ≤0.05mm alignment error for multi-cavity parts.

Multi-variant low-volume products (e.g., automotive interiors): Adopt slide-type two-color machines with ≤30-minute mold change 

to handle frequent style switches.

Equipment integrates automation (6-axis robots + vision inspection) and constant-temperature cooling (±1℃ fluctuation) to reduce 

human error and dimensional deviations.

2. Efficient Production Flow Optimization

Smart scheduling improves equipment utilization and shortens lead times:

MES-based planning: Prioritize orders; assign complex parts (e.g., medical components) to stable production periods, achieving ≥85% OEE.

Rapid changeover: Preheat next batch molds and input parameters during current production, limiting downtime to ≤20 minutes. Shared

 frames with quick-change inserts enable ≥70% mold reuse for similar products.

3. Full-Lifecycle Quality Control

Close-loop management from raw materials to finished products ensures consistency:

Incoming inspection: Test melt flow rate and density for each material batch to match prototyping standards.

In-line testing: Vision systems detect burrs or color defects (0.01mm precision) with real-time rejection.

Traceability: Unique QR codes link raw material batches, parameters, and inspection data; critical dimensions are laser-scanned every 

2 hours (tolerance ≤0.03mm).

4. Cost Optimization Strategies

Reduce costs through mold, material, and energy efficiency:

Molds: Multi-cavity designs (e.g., 16-cavity phone case molds) boost output to ≥50,000 units/shift.

Materials: Long-term supplier agreements stabilize prices; loss-in-weight feeders limit waste to ≤3%.

Energy: Servo-driven machines with heat recovery cut energy use by ≥25%; 90% cooling water recycling reduces consumption.

Total unit cost is lowered by 15-20% while maintaining quality.

Summary

This integrated solution links rapid prototyping (via efficient validation) and mass production (via stable scaling), shortening 

time-to-market by over 30%. It suits two-color injection needs across consumer electronics, automotive, and medical industries, 

ensuring both speed and reliability.