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Last year, a European customer reached out to us with a recurring issue on their production line. They were using sunflower husks to make biomass pellets, but the finished pellets were too dark.
The customer needed lighter, more natural-looking pellets but didn't want to compromise production efficiency, ring die life, or costs. We provided a customized solution that improved pellet color while maintaining performance.
We know there are many factors to produce good pellets，however，as pellet mill ring die supplier，we will try to optimize ring die for pellet mill.
After thoroughly reviewing their production process, we quickly identified the root cause and implemented several engineering improvements that not only solved their problem but also helped build a lasting business relationship.
The Challenge: Why Were the Pellets Too Dark?
The customer’s main concern was the dark color of the pellets, but the issue went beyond that — they needed a solution that would improve color without affecting the production rate, die life, or cost.
The dark pellet issue was primarily caused by overheating, resulting from the high compression ratio in the original ring die. The customer wanted to improve pellet appearance while maintaining production efficiency.
In the pelleting process, the material’s residence time in the die plays a crucial role in pellet quality. A high compression ratio leads to excessive friction and heat buildup, causing darker pellets. By adjusting the compression ratio and optimizing other factors, our engineering team solved the issue. We didn’t just modify the compression ratio; we took a holistic approach to optimize the entire process.
The Hayne Solution: Technical Optimization for Sunflower Husk Pellets
Our solution wasn’t just a quick fix. We made several technical adjustments based on the unique characteristics of sunflower husks, improving pellet color without sacrificing production efficiency.
Key adjustments to compression ratio, hole design, and lubrication allowed the pellets to be lighter and smoother while maintaining optimal production output and die life.
Here’s a breakdown of the optimization areas and the specific technical adjustments we made:
| Optimization Area | Technical Adjustment | Result |
|---|---|---|
| Compression Ratio | Adjusted L/D ratio to better suit sunflower husk | Reduced dwell time, lighter pellet |
| Tapered Hole Design | Added cone angle at the inlet for smoother material flow | Lowered friction, reduced overheating |
| Hole Type & Layout | Used stepped and mixed-length holes | Improved throughput and pellet shape |
| Heat Treatment & Finish | Vacuum heat treatment + fine polishing | Reduced surface friction and carbonization |
| Open Area Ratio | Optimized based on machine and material flow | Balanced output and temperature control |
| Lubrication Advice | Recommended high-temp grease for roller-die interface | Smoother running and longer service life |
These adjustments not only improved pellet color but also ensured the process remained efficient and cost-effective.
The Result: A Satisfied and Returning Customer
After installing the customized Hayne ring die, the customer immediately saw noticeable improvements in pellet color after just a few hours of production. The pellets were lighter, cleaner, and exactly what they needed.
The customer was so pleased with the results that he scheduled a video call to personally thank our team. Even better, he has continued to reorder Hayne ring dies for his sunflower husk production.
Conclusion: Why Customized Solutions Are Key to Pelleting Success
At Hayne, we understand that one-size-fits-all solutions don’t work in pelleting, especially for high-fiber materials like sunflower husks. This case highlights the importance of customized die designs to both the material and production goals.
Our technical solution didn’t just solve the customer’s immediate problem but also helped us build a long-term relationship. It proves how understanding unique customer challenges and offering targeted solutions can lead to lasting success.
👉 Need help optimizing your pelleting process? Let’s talk.
📩 Contact us for a custom-designed ring die solution that fits your material, machine, and production goals.
