Capsule Filling Defects | CapsCanada

Producing high-quality capsule shells is just the first step in delivering a flawless product. The next critical stage—encapsulation and filling—presents its own set of challenges. Capsule Defects such as cracked capsules, bad joins, or dented ends can disrupt production efficiency, lead to costly rework, and damage customer confidence.

In this blog, we’ll explore the most common defects during the encapsulation process and provide actionable solutions to help you eliminate waste and improve production efficiency.

Common Defects During Encapsulation and Filling

1. Dents 

Capsule domes are indented 

What Causes It?

• Excessive closing pressure.
• Excessive fill material

How to Solve It:

• Capsule length adjustment: Ensure the capsules are adjusted to fit within the proper gap of the go no-go gauge
• Capsule fill volume: Overfilling is a common root cause of denting. Use of elongated capsules can provide the additional space you need. 
  
  

2.  Cracks

Capsules crack during or after the filling process.

What Causes It?

• Brittle capsules due to poor storage conditions.
• Hygroscopic fill material  .

How to Solve It:

• Storage optimization: Store capsules at 40–60% relative humidity to maintain flexibility.
• Capsule selection: Avoid using gelatin based capsules with hygroscopic fill. HPMC capsules are much less  prone to cracking.
  
  

3. Telescoped Capsules

The cap and body become misaligned during joining.

What Causes It?

• Misalignment of the upper and lower capsule tooling 
• Abrasive fill material 

How to Solve It:

• Properly aligned tooling: Ensure upper and lower segments and carriers are aligned with proper use of alignment pins.
• Particle size: All powder for encapsulation should pass through a 30 mesh screen prior to filling. 
  
  

4. Dusty Capsules

Capsules have powder residue on their surfaces after filling.

What Causes It?

• Poor slug formation
• Insufficient dust collection at polisher

How to Solve It:

• Slug formation: Use correct dosing disc and tamping sequence to optimize powder slug
• Dust collection: Use adequate dust collection at polisher and at cleaning station
  
  

5. Empty Capsules

Capsules exit the production line without any fill material.

What Causes It?

• Poor capsule separation
• Missing empty capsule eliminator

How to Solve It:

• Use capsules with lighter pre-lock force and ensure adequate vacuum pressure.
• Restore and properly adjust faulty capsule ejection equipment and use an empty capsule eliminator on the polisher.
  
  

6. Damaged Band

Sealing bands on capsules are incomplete or distorted.

What Causes It?

• Incorrect sealing parameters (temperature, speed, or alignment).
• Fill material
  
  

How to Solve It:

• Sealing optimization: Calibrate temperature, speed, and band position settings for consistent band application.
• Material: Ensure proper viscosity and temperature of fill material

Capsule Defects with Images

At CapsCanada, we provide a downloadable resource that showcases the most common types of capsule defects with clear images and technical explanations. This guide is designed to help quality and production teams quickly identify each capsule defect and understand its root causes.

Conclusion

During encapsulation, even minor defects can result in significant losses. By implementing preventive measures such as equipment calibration, real-time monitoring, and proper material handling, manufacturers can overcome challenges like cracks, bad joins, and dusty capsules.

Want personalized advice to address specific challenges in your production line? Contact us today to learn more!

Lyfe Group: Quality Beyond Capsule Manufacturing

Lyfe Group is a global network of capsule and finished dosage form innovator companies committed to advancing consumer health. We deliver high-quality gelatin, HPMC, and specialty capsules designed for today’s most demanding nutraceutical and pharmaceutical applications.

With a strong foundation in R&D, manufacturing excellence, and technical expertise, Lyfe Group offers unmatched value across the capsule supply chain. From standard gelatin formats to clean-label options and advanced delayed-release capsules, our solutions help brands create products that stand out and perform.

Whether you are exploring capsule options or need help with technical optimization, Lyfe Group provides comprehensive solutions and expert guidance worldwide.

Learn more and connect with our global team at the official Lyfe Group website.