How to avoid blockage of ring die hole of pellet machine
- The pellet machine mold needs to be polished. The cause of the blockage of the new ring die is different from that of the old one. Some new molds will have defects in the mold hole during the drilling process. The inner surface of the hole may appear smooth. However, usually the drilling process also produces small scratches. Even these small scratches will produce enough resistance during the manufacture of particles, resulting in mold
Head clogged. Keep in mind that if the rollers of the pellet machine cannot produce enough force to overcome the resistance of the die holes, it will cause blockage. Usually use a fairly loose biomass material (I prefer to use wheat bran), about 10-15% vegetable oil and about 1-2% fine sand. You mix this material thoroughly, and then slowly and repeatedly process it in a pellet machine. This polishing material will help clean the surface of the mold hole and eliminate corrosion.
Expert tip: Use less polishing materials. If the frequency of use is too high, the surface of the mold and the pressure roller will be worn, thereby shortening its service life. Once the material guide on the mold is worn out, the compression ratio on the mold will not be suitable for producing high-quality pellets.
- Raw material granularity. Make sure that the particle size of the raw material is smaller than the diameter of the die hole. For example, a ring die with an aperture of 6mm uses a 5mm hammer mill screen to produce 6mm wood pellets. Expert tip: It is also necessary to ensure that there is no contamination in the raw materials (stone/metal). These will not only cause blockage of the die holes, but also cause serious damage to the pellet machine itself. This may include damage to the gearbox or motor.
- Raw material moisture. It is very important to control the moisture content of the raw material when making wood pellets. The ideal moisture content of the raw material is less than 15%. If the moisture content is too high, such as 20%+, it will easily cause particles when it enters the pellet machine. The mold hole is blocked.
Expert tip: Even if you prepare raw materials with ideal particle size and moisture content, you should also consider using granular binders. Particle binders can help the process and reduce the chance of clogging of the pellet machine die.
4. It is recommended to feed the pellet machine slowly to avoid blockage of the mold. When the pellet machine works, there will be a certain temperature, when it exceeds 80 degrees Celsius, the natural lignin in the wood will melt and bind the pellets together. However, if the raw material of the pellet machine is fed into the mold faster than the processing speed of the raw material, it is easy to block the mold before the pellet machine reaches this operating temperature. You have to make sure that there is enough material in front of the granulation room, but do not completely cover them. Expert tip: The pellet manufacturing process generates heat, which releases the moisture in the raw material. Filling the pellet machine processing chamber with raw materials prevents the escape of moisture (steam). This steam is then absorbed by the incoming raw materials. This means that raw materials with moisture higher than 15% can cause die blockage. Therefore, only feed the pelletizer at a rate that can be processed.
5、If you have finished making wood pellets, add a large amount of vegetable oil to the mixture in the last few minutes of the operation. This will leave a soft oily material in the mold, which will make it easier to start making pellets again next time.
How to avoid blockage of ring die hole of pellet machine? It is only for the reference of the majority of the users of the granule machine.