Reasons that caused low capacity of the feed pellet mill.
Reasons that caused low capacity of the feed pellet mill
1. Materials factor
1) The finer the materials are, the easier to absorb the steam, the easier to adjust the moisture, the higher the capacity;
The material powder can’t be too fine, if too fine, the final pellets will be easy to break;
The material powder size shouldn’t be bigger; If too big, it will increase the friction between the die and the roller, decrease the capacity;
So the suitable powder size to make pellets, for chickens, the 3.5mm screen should be selected to the hammer mill;
2) If the moisture of the raw materials is too high, and you reduce the amount of the steam, it will be difficult to increase the temperature, thus to affect the final capacity and quality of the pellets;
Meanwhile, if the moisture of the raw materials is too high, it will make it difficult to do the steam condition work and easy to cause the material slip between the inner wall of the ring die and roller; And this will also cause the materials blocking the holes of the ring die.
So make sure that before do the steaming the materials, make sure the moisture of the raw materials is less than 13%
3) Material components
(1) The higher the protein contained in the raw materials, the higher capacity;
(2) The higher the starch content in the raw materials, the higher capacity, on condition that while steaming, the moisture is between 16%-18%, and the conditioning temperature is above 80℃; Otherwise, the Starch gelatinization degree will be bad which will cause the final pellets very fragile, or can’t be made to pellets;
If you dry the corn before steaming, the final capacity will be lower;
(3) Adding small amount oil (0.5%-1%), it will reduce the friction inside the machine, and make it easier to let the pellets out of the ring die hole, thus increase the final capacity;
However, if the oil amount is higher than 2%, it will loose the pellets, make it difficult to pellets, thus reduce the capacity;
(4) Crude fiber adding amount should be 3%-5%, it will help making pellets and reduce the breaking, thus increase the capacity;
However, if the crude fiber amount is higher than 10%, the materials will be difficult to stick together, thus affect the hardness of the final pellets and the pellets forming rate, and it will also increase the friction, lower the final capacity;
(5) Inorganic mineral feed almost no adhesive power, granulating performance is poor, can affect the output of granulating. Therefore, when a high content of inorganic qualitative, usually to add a small amount of adhesive materials (such as molasses) to improve the granulating performance, increase the capacity.
2. Operation factor
1) After steaming, the moisture should be 15%-16.5%. In the actual production, you can pick some powders from the pellet machine(before entering the pelleting chamber), squeeze them and they can be shapes like a ball; when you open your hand, they can loose;
When the moisture after steaming is higher than 18%, the materials will be slip between the inner wall of the ring die, or even no pellets can be made, which lower the capacity;
If the moisture after steaming is less than 14%, the friction between the materials and the machine will be bigger, thus reduce the capacity;
2) The distance between the ring die and the rollers has big effect on the quality of the final pellets. Normally, the distance should be 0.05-0.3mm.
When the distance is bigger than 0.3mm, the materials amount will be too thick, and difficult to spread evenly, which will lower the capacity;
When the distance is less than 0.05mm, the friction will be very large and damage the machine.
In the actual operation, to confirm whether you have adjusted to the suitable distance, you rotate the ring die and the ring die almost touch the roller, check whether the ring die can drive the roller, and when the ring die is rotating, the roller sometimes can rotate with the ring die, sometimes can’t.
3) The cleanness of the ring die hole. There are some iron filings and oxide inside the hole, so before using, you need to polish them, to make the holes smoothly, thus to reduce the friction and increase the capacity.
The polishing methods:
(1) use some tool that are smaller than the hole size, to clean the iron filings;
(2) Fix the ring die, and on the material feeding side add some oil, adjust the distance between the ring die and the roller;
(3) Using 10% fine sand, 10% soybean meal powder, 70% 10% rice bran, and 10% oil, after fully mixed, this material is called abrasive material; then start the pellet machine, put them into the pellet machine, after 20-40min, make sure that 90% of the holes on the ring die have pellets come out;
4) Check the material feeder inside the pelleting chamber door; if this feeder is abrasion, the material amount into the pellet machine will decrease, thus reduce the capacity; need to change a new one;
5) The ring die block is mainly caused by poor pelleting performance materials, such as the high fiber content, moisture too high, moisture too low, etc. Or after pelleting, you did not use the abrasive material to clean the holes. Whenever the hole is blocked, using the tools to clean the holes immediately;
6) The feeder of the pellet machine, speed is too slow, the capacity will also decrease;
3. The spare parts factors:
1) Ring die installation error, will cause the excessive wear and uneven pelleting, it also even causes the ring die displacement, decrease the capacity’
2) The cutter is too close to the ring die, which will increase the powder amount, decrease the capacity; when adjusting, make sue: pellet length: pellet size=1-2:1
4. The steam factor
Before the steam enter the conditioner, remove the condensate water, With a pressure reducing valve, turn it into a low pressure dry steam to improve the conditioning effect;
After reducing pressure, the steam pressure should be higher than 0.2Mpa, temperature is higher than 120℃.