Many customers will encounter the problem of large differences in the weight of extruded tablets during use. Here we analyze the causes and solutions to the entire problem.
1. The distribution of particle size is uneven, and the particle flow rate is different during tableting, resulting in uneven particle size filled into the middle die hole. If there are too many coarse particles, the tablet will be light, and if there are too many fine particles, the tablet will be heavy.
Solution: The granules should be mixed or screened to remove excess fine powder.
2. If fine powder adheres to the punch and causes hanging punching, the tablet weight will vary greatly.
Solution: At this time, the lower punch is not rotating flexibly. You should check it in time, remove the punch die, and clean the lower punch and middle die holes.
3. The particle fluidity is not good, and the amount of particles flowing into the middle die hole is sometimes large and sometimes small, causing the tablet weight to be too different and exceed the limit.
Solution: Re-granulate or add appropriate flow aids such as micro-powder silica gel to improve the fluidity of the granules.
4. Particle stratification.
Solution: Solve particle stratification and reduce particle size difference.
5. Use materials with larger particles for smaller tablets.
Solution: Choose appropriately sized particles.
6. The hopper is blocked. This phenomenon often occurs with drugs with strong viscosity or hygroscopicity.
Solution: The hopper should be cleared, the tableting environment should be kept dry, and flow aids should be added appropriately to solve the problem.
7. The storage capacity of materials within the materials varies greatly.
Solution: Control within 50%.
8. The feeder is unbalanced or not installed in place, causing uneven filling.
9. The scraper board is uneven or poorly installed.
Solution: Level.
10. With a forced feeder, the speed of the wheel of the forced feeder does not match the speed of the turntable.
Solution: Adjust to the same tune.
11. The fit between the punch and the middle die hole is not good. For example, a lot of powder leaks between the outer periphery of the lower punch and the wall of the die hole, causing the lower punch to "push", resulting in insufficient material filling.
Solution: The punch and middle die should be replaced.
12. The length of the undershoot is different and out of tolerance, resulting in uneven filling volume.
Solution: Repair the difference to within ±5μm.
13. For the lower punch with damping, the damping force adjusted by the damping screw is not good.
Solution: Readjust.
14. The filling track is worn or the filling mechanism is unstable.
Solution: Replace or stabilize.
15. In pursuit of output, the turntable rotates too fast and the filling amount is insufficient.
Solution: Especially when pressing large pieces, the speed should be appropriately reduced to ensure sufficient filling.
16. The tablet press has excessive vibration, loose structure, unreasonable assembly or reassembly.
Solution: The tablet press setting pressure is too high, reduce the pressure.
