Factors Affecting The Service Life of Injection Molds

1. Mold Material & Heat Treatment

• Material Selection: High-quality steel (e.g., H13, S136, P20) with good hardness, toughness, and wear resistance extends mold life.

• Heat Treatment: Proper quenching and tempering improve hardness and reduce brittleness.

• Surface Treatments: Coatings like chrome plating, nitriding, or TD treatment enhance wear and corrosion resistance.

2. Mold Design & Structure

• Parting Line Design: Poor alignment causes flash and wear.

• Gating System: Poorly designed gates increase injection pressure, stressing the mold.

• Cooling Channels: Uneven cooling leads to thermal stress and cracking.

• Ejection System: Misaligned ejector pins or sliders cause scratches and damage.

3. Injection Molding Process Parameters

• Injection Pressure/Speed: Excessive pressure accelerates wear.

• Melt Temperature: Too high temperatures degrade the mold steel over time.

• Holding Pressure & Time: Prolonged pressure increases mechanical stress.

• Cooling Time: Insufficient cooling may cause part sticking and mold damage.

4. Maintenance & Operation

• Cleaning & Lubrication: Residue buildup causes scratches; lubricating moving parts (e.g., guide pins) reduces wear.

• Rust Prevention: Moisture or corrosive plastics (e.g., PVC) require protective coatings.

• Proper Handling: Rough ejection or mishandling shortens mold life.

5. Plastic Material Properties

• Abrasive Fillers: Glass or carbon fibers increase wear.

• Corrosive Additives: Flame retardants or acidic compounds degrade steel.

• Thermal Stability: Poor heat resistance leads to residue buildup.

6. Production Environment & Management

• Production Volume: Continuous high-volume runs cause thermal fatigue.

• Mold Storage: Improper storage leads to rust or damage.

• Regular Maintenance: Polishing and minor repairs prevent major failures.

7. Other Factors

• Mold Complexity: Micro-features or thin walls are more prone to damage.

• Expected Lifespan: Standard molds last 100,000–1,000,000 cycles, while high-precision molds may require refurbishment after just 50,000 cycles.

How to Extend Mold Life?

✔ Use high-quality mold steel with proper heat treatment.
✔ Optimize cooling channels to reduce thermal stress.
✔ Follow strict maintenance (cleaning, lubrication, rust prevention).
✔ Adjust process parameters based on plastic material.

By controlling these factors, manufacturers can maximize mold lifespan, reduce downtime, and improve cost efficiency.