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4. Screening of the damp mass:
The damp mass is passed through sieve No. 6 or 8 (1.7–2 mm aperture) to form wet
granules.

5. Drying of granules:
The wet granules are dried in a hot air oven or fluidized bed dryer at 40–60°C until the
moisture content is 1–2%.

6. Sizing of dried granules:
The dried granules are passed through sieve No. 16 or 20 to obtain uniform granule size.

7. Addition of lubricants and glidants:
After drying and sizing, the external phase (lubricant, glidant, remaining disintegrant,
color) is added and mixed gently.

8. Compression:
The prepared granules are compressed using tablet press.

Important Notes:

• The wet mass consistency is critical; too dry → weak granules; too wet → large lumps.

• Granule size influences flow and uniformity.

• Optimum drying avoids overwetting or overdrying, which can cause friability or poor
compaction.

I-b- Dry granulation:
It's used for moisture and heat sensitive drugs that cannot undergo wet granulation.

Principle:
The powder is compressed into large slugs or sheets, then broken down into granules and
compressed into tablets.

Steps:

1. Weighing and mixing of ingredients.

2. Compression into slugs (slugging) or compaction by roller compactor.

3. Screening and milling of slugs to produce granules.

4. Addition of lubricant and glidant.

5. Compression.

Advantages:
• No heat or moisture used.
• Simple and economical.

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