Pellet Press Die Metals for Pellet Press Machines

Die Metals

Pellet press dies are made from several different types of metal, each with different advantages and disadvantages. Pellet press dies must be resistant to abrasion, strong to handle the forces of pellet production, corrosion resistant and give a good productivity. The ideal die of pellet press machine will be strong with low wearing and corrosion characteristics, and give maximum productivity.

Carbon Steel Alloy is one of the good die metals
Carbon Steel Alloy: These pellet press dies are heat treated and are the strongest pellet press dies available, their key advantage therefore is good abrasion and breakage resistance. Their disadvantages are in corrosion resistance and productivity. Carbon steel rusts, and surface corrosion collects on the inside of the die holes, this corrosion can affect pellet press die blockages and productivity. Before pellet production can begin a polishing agent must be run through the pellet press machines, for example wheat bran and vegetable oil. This will remove the surface corrosion, and then pellet production can begin. A loose oily material must also be processed at the end of production to remain in the pellet press die before the next production cycle. If the feedstock is left in the die, as the die cools the material forms a hard dense pellet in the die. The moisture released as the pellet cools and dries penetrates the die surface and corrosion forms, locking the pellet in the die of pellet press machine. Once this has occurred drilling each hole in the pellet press die is required to remove the material. Productivity for carbon steel dies is also lower than with other die metals. The surface finish on the inside of the die hole affects the resistance as the material passes through the dies of pellet press machines. Carbon steel dies partly due to the corrosion issue generally have a rougher finish; this increases resistance as the material passes through the die, resulting in a lower productivity. However this can have a benefit on the quality of pellet press machines, which can produce a harder pellet.

In summary pellet press machines with carbon steel dies may have their disadvantages with regards to corrosion resistance and productivity, but they are the strongest dies, with the longest life and are by far the cheapest. Carbon steel dies are seen as a good all-rounder and used for most materials, particularly highly abrasive materials.