Which Pellet Mill to Choose? Ring Die or Flat Die?

Nowadays, pellet mill in the market is mainly divided into ring die pellet mill and flat die pellet mill. These two main types both have their own advantages and disadvantages respectively. Therefore, which pellet mill to choose? The ring die pellet mill or the flat die one becomes concern of many people.

Flat Die Pellet Mill

Flat die pellet mill comes earlier in the market than ring die pellet mill. It is designed at the turn of 20th centuries based on flat dies. Its primary structural feature is that its die is horizontal with a series of rollers above it. When making pellets, the powders of raw material fall down into the space between the flat die and the rollers. Then the rollers compress these powders into the small holes in the flat die to form pellets. As soon as the pellets emerge on the other side of the flat die, a series of knives will cut them into the same determined length immediately. Thus, the final pellets with the same length are made. Flat die pellet mill is mainly applied in individual use and home usage, as it is easy to move and operate. Flat die pellet mill can also be divided into two types: rotating roller flat die pellet mill and die-turned flat die pellet mill.

Rotating Roller Flat Die Pellet Mill

Rotating roller flat die pellet mill refers to the flat die pellet mill whose die is stationary and the rollers are rotating while making pellets. The rotating rollers and the pushing plate beside them push and move the powders of raw material evenly distributed. As the rollers rotate, they press these powders into the holes of the die to form pellets.
Die-turned Flat Die Pellet Mill
Die-turned flat die pellet mill refers to the flat die pellet mill whose die rotates while rollers are stationary when making pellets. As the powders of the raw material fall into the area between the die and the rollers, the die rotates to move these powers under the rollers to be compresses into the holes in the die to form pellets.

Advantages of Flat Die Pellet Mill

Flat die pellet mill is the first choice for starters and for home and individual usages. It enjoys many advantages, like: small size, compact structure, low power consumption, low noise, easy operation and maintenance. Moreover, if the die or rollers of the flat die pellet mill need to be changed in the later use, a single person can totally handle it.

Ring Die Pellet Mill

Ring die pellet mill adopts the forced feeding method, and the powders of raw materials enter the pelletizing chamber through high speed rotating. And the scrapers in the ring die pellet mill distribute the powders of raw materials over the inner surface of the rotating ring die. Then a series of rotating rollers compress the powders into the holes in the ring die to form pellets.

Flat Die and Ring Die Pellet Mill’s General Obvious Comparison

Capacity: Generally speaking, the capacity of ring die pellet mill is larger than flat die pellet mill.
Price: Flat die pellet mill’s price is usually lower than that of ring die pellet mill.
Feeding: The feeding method in the flat die pellet mill relies on gravity of the powders of raw material. While the ring die pellet mill forces the powders into the pelletizing chamber of the ring die pellet mill.
Final Pellets: The final pellets of flat die pellet mill enjoy higher forming rate than those of ring die pellet mill. This is mainly because final pellets’ discharging method is different. The ring die pellet mill throws final pellets out with centrifugal force, thus making final pellets break easily.

With all the comparisons above, you probably know how to choose a pellet mill according to your needs and budget. However, if the capacity of flat die and ring die pellet mills are the same, then, what should you think about? And which kind of pellet mill should you choose?

In this case, the price of ring die pellet mill may be still a little higher than that of the flat die pellet mill, as the former’s cost of manufacturing is usually higher. If the little difference of price doesn’t bother you, then the next point must come into your mind. That is the operation and later maintenance of the pellet mills. A single person is enough for flat die pellet mill, while the ring die pellet mill probably needs two or three people as its die and rollers are much heavier. Consequently, you need more time and person when changing the rollers or ring die.