Causes and treatment methods of tablet weight out of tolerance of Shanghai Lvyi tablet press

1 The particle size distribution is uneven, and the flow rate of the particles is different during tableting, resulting in uneven particle size filled into the die hole. The particles should be mixed or sieved to remove excessive fine powder. 2. When the fine powder adheres to the punch and causes the punch to hang, the difference in tablet weight can be large. Solution: At this time, the rotation of the lower punch is not flexible. It should be checked in time, remove the die, and clean the lower punch and the middle die hole. 3. The fluidity of the granules is not good, and the amount of granules flowing into the middle die hole is sometimes more and sometimes less, which causes the difference in tablet weight to be too large and exceed the limit. Solution: Re-granulate or add suitable flow aids such as micro-powder silica gel to improve the fluidity of the particles. 4 Particle layering. Solution: Particle stratification to reduce particle size difference. 5 Smaller tablets use larger particle materials. Solution: choose the appropriate size of particles. 6 The hopper is blocked, which often occurs with viscous or hygroscopic drugs. Solution: The feeding hopper should be dredged, the pressing environment should be kept dry, and a glidant should be added appropriately to solve the problem. 7. The material storage volume in the material varies greatly. Solution: Control within 50%. 8 The feeder is unbalanced or not installed in place, resulting in uneven filling. Solution: Balance the feeder or install it in place. 9 The fit between the punch and the die hole is not good. Solution: For this, the punch and die should be replaced. 10 In pursuit of output, the rotating speed of the turntable is too fast, and the filling volume is insufficient. Solution: Especially when pressing large tablets, the speed should be properly reduced to ensure sufficient filling. 11 The vibration of the tablet press is too large, the structure is loose, the assembly is unreasonable or reassembled; the setting pressure of the tablet press is too high, the solution: reduce the pressure.