6 Strategies to Reduce Cost of Plastic Parts in Injection Molding

As a sourcing or purchasing manager, reducing costs while maintaining quality is one of your top priorities. When it comes to plastic injection molding, there are several strategies you can use to cut down expenses without sacrificing the performance of your plastic parts. Here are six practical ways to optimize costs in your plastic injection molding projects:

Key Cost Reduction Strategies:

• Choose the Right Material: Opt for materials that offer the best balance between cost and performance.

• Simplify the Design: Work with your design team to remove complex features that drive up production costs.

• Improve Process Efficiency: Make small adjustments to the production process to increase output without additional resources.

• Reduce Waste: Implement better material management to minimize waste and maximize material usage.

• Work Closely with Suppliers: Negotiate better pricing and collaborate on cost-effective solutions.

• Focus on Continuous Improvement: Regularly review and refine processes to keep reducing costs over time.

1. Choose the Right Material

Selecting the right material can make a big difference in your costs. For example, if you’re currently using a high-performance plastic that costs $10 per kilogram, consider whether a similar material that costs $8 per kilogram could do the job just as well. By switching to the less expensive material, you could reduce your material costs by 20%, all without compromising the quality of your parts.

This simple step can help you achieve significant savings, especially in large production runs.

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2. Simplify the Design

The design of your plastic parts plays a huge role in the overall cost. For instance, if your part has a complex feature like an undercut that requires special tooling, it’s going to be more expensive to produce. By working with your design team to simplify the part—say, by removing the undercut—you could save thousands of dollars in tooling costs and make the production process faster and more efficient.

Simpler designs not only lower costs but also speed up production, allowing you to meet tight deadlines and reduce labor expenses.

3. Improve Process Efficiency

Improving how the injection molding process is carried out can also lead to cost savings. For example, if you can reduce the cooling time by just a few seconds per cycle, you can produce more parts in the same amount of time. Let’s say you currently produce 1,000 parts per day with a cycle time of 60 seconds. Cutting the cycle time by 5 seconds could boost your output by an additional 100 parts per day.

This means you’re getting more parts without spending more money on extra resources, effectively reducing your per-unit cost.

4. Reduce Waste

Waste during production is money lost. If you’re seeing a waste rate of 10% in your material usage, there’s room for improvement. By implementing better material management practices, optimizing the runner and gating systems, and reusing scrap material, you could cut your waste rate in half. For example, reducing waste from 10% to 5% in a production run that uses 1,000 kilograms of material per month could save you 50 kilograms of material.

Less waste means direct savings, which adds up over time, especially in high-volume production.

5. Work Closely with Suppliers

Building strong relationships with your suppliers can lead to cost reductions as well. For instance, negotiating better pricing or bulk purchase discounts on materials can help you save significantly. If your annual material cost is $500,000, even a small 5% discount could save you $25,000. Additionally, collaborating with tooling suppliers to find cost-effective solutions can lower your upfront costs and reduce maintenance expenses down the line.

Good supplier relationships are key to securing the best deals and finding cost-effective solutions that meet your needs.

6. Focus on Continuous Improvement

Continuous improvement isn’t just a buzzword—it’s a way to keep costs down over time. By regularly reviewing and refining your processes, you can identify areas where efficiency can be improved. For example, setting up a team to focus on process improvements could help you reduce overall manufacturing costs by 10%.

Ongoing efforts to streamline production will keep you ahead of the competition and help you meet your cost reduction targets year after year.

Conclusion

Reducing costs in plastic injection molding doesn’t have to mean compromising on quality. By focusing on smart material choices, simplified designs, process efficiency, waste reduction, supplier collaboration, and continuous improvement, you can achieve significant savings. As a sourcing or purchasing manager, these strategies will help you meet your cost targets, making your projects more profitable and your company more competitive.