Tableting Problems (Trouble Shooting)

Question 1

Give 6 possible reasons why your tablets have inconsistent weight

Answer 1

1. Variations in punch length
2. Inconsistent granule
3. Incorrect setting of feeder paddle speed
4. Die not filling
5. Bad scrape off
6. Empty feed frame

Question 2

Give 6 solutions to your tablets’ inconsistent weight

Answer 2

1. Replace or regrind punches to the appropriate length
2. Improve granule/mixing technique
3. Adjust paddle speed as necessary
4. Press “running too fast”
5. On mark IV machines, check that scrapper is not beyond edge and resting on feeder platform
6. Check hopper/feeder to ensure granule flows freely

Question 3

Give 3 reasons why your tablets are sticking to the upper punches

Answer 3

1. The upper punch is damaged
2. High level of moisture in the granules
3. Insufficient lubricant
4. Insufficient compaction force
5. Pressure roll bounce

Question 4

Name 5 ways to make your tablets stop sticking to your upper punches.

Answer 4

1. Refurbish or replace punches
2. Dry granules in oven, sieve and relubricate. Adjust room humidity.
3. Add or increase lubricant
4. Increase weight and/or reduce thickness within allowable tolerance
5. Pressure roll freedom and face condition

Question 5

Why will you see a double impression on your tablets?

Answer 5

Worn punch holding pads

Question 6

How can you solve the problem of double impressions on your tablets?

Answer 6

Replace worn punch holding pads

Question 7

Why would you see a “flash” on a tablet edge?

Answer 7

1. Worn punches or die
2. If tampered dies are being used tablet being compressed in tapered section of die

Question 8

What causes variations in tablet thickness/hardness?

Answer 8

1. Variations in upper or lower punch lengths
2. Inconsistant granule
3. Worn pressure roll

Question 9

How do you make sure your tablets are of the thickness/hardness?

Answer 9

1. Replace or grind punches to length
2. Improves the granules
3. Replace worn pressure rolls

Question 10

Why would the top of your tablet be cracked/split?

Answer 10

1. Punches may be damaged
2. Tablet may be too dry

Question 11

How can you stop your tablets from being cracked/split?

Answer 11

1. Replace damaged punches
2. Add moisture, remix, granulate, lubricate

Question 12

What causes tablets breaking on take off and how will you avoid it?

Answer 12

1. Take off plate incorrectly set - Check and rest
2. Lower punch ejection height - Check and reset
3. Spend too high for particular material - Reduce speed until acceptable tablet is obtained.
4. Not enough binder in the mix - Increase
5. Granules too dry - Increase moisture levels

Question 13

How do you solve the problem of the tablet binding on the die?

Answer 13

1. Replace worn out dies
2. Dry sieve high moisture granules
3. Increase lubrication

Question 14

Why would your tablets have split in half upon lamination?

Answer 14

1. Incorrectly set take off plate
2. Lower punch ejection incorrectly set
3. High speed

Question 15

What would cause capping?

Answer 15

1. Air entrainment
2. Excess pressure
3. Too rapid expansion

Question 16

How would you solve the problem of capping?

Answer 16

1. Compress higher in the die
2. Employ precompression
3. Reduce weight and/or increase thickness within allowable tolerances
4. Taper dies