Die and roller (stainless steel)

The 21 Stages of Die Production Reflect the Quality of Our Products  

Based on American CPM technology

1. Receiving raw blanks 8. Reaming 15. Final reaming

2. Heat treatment 9. Slotting 16. Grinding

3. Rough machining 10. Bolt hole drilling 17. Cleaning

4. Die groove machining 11. Quenching 18. Air-blast surface polishing

5. Drilling 12. Final machining 19. Cleaning

6. Hole refinement and testing 13. Die flange machining 20. Final inspection

7. Countersinking 14. Re-finishing 21. Packaging

In general, the right choice of alloy has a major effect on die quality and life. Zhengchang dies and rollers are made of corrosion-resistant alloy steel. To ensure there is no oxide scale in the die holes, heat treatment is carried out in multi-purpose vacuum furnaces. Thanks to uniform heat treatment, the die is very hard and wear-resistant.

Correct Use of Dies and Rollers

The most important consumable part in a feed mill is the die in the pellet mill machine. Feed quality, durability and the appearance of the final product all depend on the die and rollers installed on the mill’s pellet mill. Die quality and precision directly affect pellet uniformity. A well-designed, high-quality die and roller guarantee uniform pellets.

Investing in high-quality dies and rollers may cost more up front, but it can reduce operating costs in the long run. Quality parts significantly cut replacement and maintenance costs. Proper repair, maintenance and use of dies and rollers are also very important, as described below:

1. Use a suitable compression ratio.

2. Install the die and rollers correctly.

3. Keep the roller properly positioned relative to the die surface.

4. Start production with a light load.

5. Open blocked holes. (Blocked holes should be under 5 percent.)

6. A new die needs a running-in period. After installing the die, and after an emergency stop, run the machine without load.

7. On-site maintenance of dies and rollers is very important.

8. For the best production efficiency, choose different rollers for different materials.

9. The best gap between die and roller is 0.1–0.3 mm and should not exceed 0.6 mm. (Within a certain range, a larger gap is better for feed quality.)

10. Replace the wear ring when wear exceeds 0.2–0.3 mm. The wear ring should also be smaller than the gear.

11. The gap between the scraper and the die cover should be less than 3–5 mm.

12. Use bolts of the correct length.

If you like, you can listen in this episode Listen to our podcast to learn more about how dies and rollers work and how to maintain, replace and install them.