Process of Dry Powder Filling in Capsule Production

Dry powder filling is a common method used in capsule production to fill capsules with powdered or granulated materials, including active pharmaceutical ingredients (APIs) and excipients. The process involves several steps to ensure accurate and uniform filling of the capsules. Here’s a detailed explanation of the dry powder filling process in capsule production:

1. Capsule Filling Machine Setup

The first step in the dry powder filling process is to set up the capsule filling machine. The machine is adjusted to accommodate the specific size and type of capsules being used. The dosing disc, which controls

the amount of powder to be filled in each capsule, is also adjusted based on the required fill weight.

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2. Capsule Separation and Orientation

Empty capsules are loaded into the capsule filling machine’s hopper. The machine separates and orients the capsules so that the open ends face upward and are ready to be filled.

3. Powder Dispensing

The dry powder formulation, which may include the API and other excipients, is fed into the machine’s powder hopper. The machine dispenses the precise amount of powder into each empty capsule through a dosing disc or other metering mechanism.

4. Tamping and Pre-compression (Optional)

In some cases, after filling the powder, a tamping or pre-compression step may be included to ensure proper settling of the powder in the capsules and to achieve more uniform filling. This step helps eliminate air pockets and improve the dosage accuracy.

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5. Capsule Closing

Once the capsules are filled with the dry powder, the machine brings together the cap and body of each capsule, sealing them to form a complete and closed capsule.

6. Quality Control

Throughout the process, regular quality control checks are conducted to ensure the capsules are correctly filled and sealed, and that the fill weights are within the specified limits. Capsules that do not meet the required quality standards are rejected.

7. Cleaning and Maintenance

After the filling process is completed, the machine is thoroughly cleaned to prevent cross-contamination between different batches or products. Regular maintenance of the machine is also performed to ensure its proper functioning and accuracy.

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8. Packaging

The filled and sealed capsules are collected and placed in suitable packaging, such as blister packs or bottles, to protect them from external factors and maintain their integrity during storage and distribution.

Conclusion

The dry powder filling process in capsule production is a precise and controlled operation. By setting up the capsule filling machine, separating and orienting the capsules, accurately dispensing the dry powder, and closing the capsules, manufacturers can produce capsules with uniform and accurate dosages. Strict quality control measures and regular maintenance of the equipment are essential to ensure the capsules meet the required quality standards and provide patients with safe and effective medications.