Pellet dies: The life of a Pellet Die
There are many variables that can play a part in the effective life of a pellet die. Some of these variables are explained below:
- The feed formulation (composition of the raw material)
- The characteristics of the raw materials used in the production of the feed
- The fat content of the feed formulation
- The particle size of the mash
- Moisture content of the mash feed before pelleting
- The thermal conditioning of the mash
- The automisation of the pellet mill
- The safety precautions implemented in the feed mill
Feed formulation: Feeds can differ greatly in their composition which can affect the life of the die. For example some feeds are highly fibrous in content while others are not such as soyameal based feeds. The fibrous the feed ingredients are generally mean that the life of the die will be shorter. For example a die producing rabbit feed (which is very fibre rich) would only last approximately one quarter of the time that a similar die producing cattle feed would. Similarly a die producing cattle feed would last less time then a similar die producing poultry feed (which is primarily corn + soya based).
Characteristics of the raw materials: Fibre content is discussed above, another factor is that any raw materials containing silica / sand would wear down the pellet die more rapidly.
Fat content of the feed: Fat in the feed helps to act as a lubricant. Feed formulae containing 1.5-2% fat would run smoother and are less abrasive, because of this.
Particle size of the mash: Better ground mash with smaller particle size is less abrasive for the pellet die.
Moisture content and thermal conditioning of the mash: A poorly conditioned mash is drier and harder to pellet.
Press control: The operator should regularly check the state of wear on the deflectors and scrapers and also the roll adjustment : to avoid uneven wear on the die and consequently inefficient pelleting. The state of wear on the conditioner paddles : to ensure efficient pre-conditioning. Steam traps and filters : to ensure that no condensate is being passed into the conditioner.
The safety precautions implemented in the feed mill: All feed mill should have grain cleaners and magnetic canisters set-up prior to all main process. If ferrous impurities were to enter the pellet mill, the pellet dies life would be reduces dramitically. It is very important that there are sufficient measures in place to ensure there are no impurities and foreign particles contained in the feed mix.