Injection molding is a cornerstone of modern manufacturing, serving industries like automotive, medical, and electronics.

This guide explores common molding types to help clients choose the best solution.

Ⅰ. Classification by Material

1. Plastic Injection Molding

Features

• Materials: ABS, PP, PE, PVC, PA66
• Advantages: Low cost, high efficiency, dimensional accuracy ±0.1mm

Applications

• Daily necessities (e.g., containers), electronic housings, medical device components

2. Rubber Injection Molding

Features

• Sulfur curing required, temperature resistance -40°C to 150°C
• Advantages: Excellent sealing, anti-aging, suitable for complex shapes

Applications

• Automotive seals, industrial shock absorbers, medical tubes

Ⅱ. Classification by Process

1. Insert Molding

Features

• Inserts (metal/plastic) placed in mold for integrated molding

Benefits

• Eliminates secondary assembly, reduces cost by 30%
• Enhances structural strength and sealing

Applications

• Plastic gears with metal inserts, smartwatch straps

2. Overmolding

Features

• Material flexibility (rigid plastic + soft rubber/metal inserts)
• Precision alignment for seamless material integration

Benefits

• Eliminates post-processing (painting/assembly), reduces pollution
• Multi-functionality (anti-slip, shock absorption, conductivity)
• Enhanced durability (bonding strength ≥6kN/m)

Applications

• Remote controls with soft-touch buttons, AR glasses anti-slip nose pads
• Surgical clamp silicone handles, sensors with metal electrodes

3. Two-Color Injection Molding

Features

• Dual-barrel machines for simultaneous molding of two materials/colors

Benefits

• Eliminates painting/stickers, eco-friendly and faster delivery
  Soft-touch design options (e.g., toothbrush handles)

Applications

• Appliance control panels, anti-slip handles for sports equipment

4. Microcellular Foaming Injection

Features

• Supercritical gas foaming reduces density by 10-30%

Benefits

• Lightweight yet strong, ideal for thin-walled parts (≥0.5mm)
• Reduces injection pressure by 20%, extends mold lifespan

Applications

• Automotive interiors, electronic device cushions

Ⅲ. Classification by Mold Structure

1. Two-Plate Mold

Features

• Basic design with single parting line

Benefits

• Lowest cost, ideal for simple geometries
• Short lead time (4-6 weeks)

Applications

• Plastic cups, trays, and flat components

2. Three-Plate Mold

Features

• Runner plate enables pin-point gating

Benefits

• Separates runners and parts automatically, suitable for mass production
• Supports multi-cavity molds (up to 96 cavities)

Applications

• Bottle caps, miniature gears

Ⅳ. Industry-Specific Applications

1. Consumer Electronics

Applications

• Smartphone casings (e.g., Apple AirPods Pro charging case)
• Wearable devices (smartwatch straps, AR glasses frames)
• Smart home devices (smart lock panels, router housings)

Technical Requirements

• Materials: High-flow PC/ABS (MFR ≥25g/10min)
• Process: Micron-level precision molding (±0.03mm tolerance)
• Surface Treatment: IMD (In-Mold Decoration) for intricate textures

2. Intelligent Manufacturing

Applications

• Robot joints (carbon fiber-reinforced PA12)
• AGV sensor housings (anti-static PC)
• 3D printer nozzles (high-temp PEEK)

Technical Requirements

• Materials: Wear-resistant POM (COF ≤0.2)
• Process: Servo-controlled molding (pressure fluctuation ±1.5MPa)
• Testing: 2M cycles without fracture

3. Semiconductor Manufacturing

Applications

• Wafer carriers (8″/12″ wafer transport boxes)
• Photolithography seals (acid-resistant EPDM)
• IC test socket housings (low-halogen LCP)

Technical Requirements

• Materials: High-purity PP (metal ions ＜10ppb)
• Environment: ISO Class 10 cleanroom
• Process: Dust-free molding (ESD removal ≥99.9%)

4. Automotive Lightweighting

Applications

• Battery pack structures, door panel brackets, aerodynamic kits

Technical Requirements

• Materials: Glass fiber-reinforced PA66
• Process: Long fiber molding (LFT-D, fiber length ≥12mm)
• Testing: SAE J826 compliant

5. New Energy

Applications

• Battery casings (Tesla 4680 module brackets)
• Solar inverter housings (IP67 waterproof)
• Charging station connectors (PA66 with high durability)

Technical Requirements

• Materials: Flame-retardant PPO (UL94 V-0)
• Process: High-temperature molding (mold temp 120°C±5°C)
• Testing: 1500+ plug cycles without wear

Ⅴ. Ulite: Precision Injection Molding Solutions

To achieve optimal results in injection molding

Three factors are critical: advanced equipment, proven experience in similar projects, and skilled personnel. With over a decade of expertise, Ulite delivers comprehensive services, including standard injection molding, insert molding, overmolding, and more.

Ulite is your trusted injection molding expert.

With over a decade of expertise, Ulite delivers comprehensive services, including standard injection molding, insert molding, overmolding, and more.Our engineers support you from design optimization and mold development to surface finishing. Backed by fully automated 24/7 production lines, we ensure fast turnaround times and consistently high-quality parts.

Ready to proceed? Share your designs for a tailored quote. Let’s bring your vision to life.