Sieve analysis is a fundamental technique for determining particle size distribution in pharmaceutical and industrial applications.
Sieve Analysis Fundamentals
Principle
Particles are separated by passing through a series of sieves with progressively smaller mesh openings. Material retained on each sieve represents a size fraction.
Sieve Construction
Sieves consist of fine wires of stainless steel, brass, or copper woven into meshes with precise aperture sizes.
Method Steps
Sample Preparation
- Obtain representative sample
- Dry if necessary
- Break up aggregates without crushing particles
- Weigh sample accurately
Sieve Stack Assembly
- Arrange sieves in order (largest aperture on top)
- Place sample on top sieve
- Secure lid
- Mount on sieve shaker
Shaking
- Set appropriate amplitude and duration
- Start shaker
- Run for specified time
- Allow system to stop completely
Weighing
- Carefully remove each sieve
- Weigh retained material
- Calculate percentages
Result Interpretation
Size Distribution
Plot cumulative percentage vs. sieve size to visualize distribution.
Key Metrics
- D10, D50, D90 values
- Mean particle size
- Span (distribution width)
Quality Control Applications
Granulation Monitoring
Verify granule size meets specifications for tableting.
Excipient Qualification
Confirm incoming materials meet particle size requirements.
Process Control
Monitor manufacturing processes affecting particle size.
Best Practices
Sample Size
Use appropriate sample mass for sieve diameter and material density.
Shaking Time
Optimize to achieve complete separation without particle breakage.
Sieve Maintenance
Regular cleaning and calibration verification ensure accurate results.