The rationality of gap adjustment directly affects the effect of the pelletizer

As an environmentally friendly granulating process, the dry granulator is a new equipment which can directly press the powder into particles, and is widely used in the pharmaceutical industry It is not necessary to add any additional water or other adhesives, especially suitable for granulation of materials prone to decomposition failure or agglomeration in case of heat and humidity In the dry granulation equipment, all parts that can contact the material are sealed, which can completely avoid the drug quality problems caused by impurities such as lubricating oil Zero waste discharge has greatly reduced the pollution of the pharmaceutical industry to the environment, and greatly improved the social image of the enterprise while improving the economic benefits of the enterprise The gap between pressing roller and ring die is one of the important parameters for the operation of dry granulator, and its adjustment process is also one of the important adjustment steps before the operation of small granulator The rationality of gap adjustment directly affects the performance of dry granulator
1 Generally, the rotation direction of the ring die is clockwise If the granulator with two pressing rollers is equipped, the eccentric convex edge of the left pressing roller shall be installed in the upper left half of the ring die when the pressing roller is installed, and the eccentric convex edge of the right pressing roller shall be installed in the lower right half of the ring die If multiple pressing roller granulators are equipped, it shall also be ensured that when the eccentric adjusting block ring rotates in the opposite direction of the die When rotating, the press roll shall move towards the direction contacting with the ring die, otherwise, it indicates that the press roll is not installed correctly, and it shall be reinstalled according to the above requirements 2 The gap between the press roll and the ring die is generally 0.3mm-0.5mm During the adjustment, the outer surface of the press roll is usually slightly contacted with the inner surface of the rotating ring die, and it is driven by the ring die to achieve similar rotation and non rotation Under normal circumstances, the gap between the two with small die hole is smaller, and the gap between the two with large die hole is larger; the gap between the new die is smaller, and the gap between the old die is larger If the gap between the press roll and the ring die is too small, the press roll and the ring die are easy to wear, and the noise is large On the contrary, the gap is too large, which will cause the difficulty of discharging
3 However, the roundness of the ring die and the press roll will be slightly deformed after heat treatment During the adjustment, the outer diameter of the press roll should be in contact with the inner diameter of the ring die, and the gap is still 0.3mm-0.5mm This adjustment is usually called jump contact adjustment If the outer diameter of the press roll is in contact with the inner diameter of the ring die, additional radial force (impact load) will be generated, and abnormal metal friction will occur Wipe your voice.