ASTM D6128-22

Overview

ASTM D6128-22 is a widely recognized standard test method developed by ASTM International for shear testing of bulk solids using the Jenike Shear Tester. This method provides procedures and apparatus guidelines for measuring key flow properties of bulk solids, including cohesive strength, internal friction, wall friction, and bulk density. The standard is vital in ensuring reliable, controlled flow of powders and granular materials from bins, hoppers, and silos in industrial facilities.

Bulk solids’ flow reliability affects productivity, product quality, and equipment safety. Flow stoppages caused by arching, ratholing, uncontrolled flows, segregation, and caking are typical issues addressed by analyzing flow properties according to this standard.

Key Topics

• Jenike Shear Tester Use: Detailed instructions for specimen preparation, applying stresses, measuring shear forces, and maintaining precise test conditions.
• Cohesive Strength Assessment: Determines the force required for the material to begin flowing after being at rest or during continuous movement.
• Wall Friction Evaluation: Tests how various wall materials affect the flow and adhesion of bulk solids in hoppers and bins, informing the selection of lining or construction materials.
• Internal Friction and Bulk Density Measurements: Provides data critical for predicting material flow, storage design, and material handling system performance.
• Time Consolidation (Aging Tests): Assesses how stored conditions over time change the resistance to flow, simulating real-world resting periods in hoppers or silos.
• Significant Digits & Data Reporting: Ensures data collection and reporting adhere to geotechnical industry best practices for precision and accuracy.

Applications

The practical applications of ASTM D6128-22 span across industries handling bulk powders and granular solids, such as food processing, pharmaceuticals, chemicals, mining, and construction materials. Key uses include:

• Bin and Hopper Design: The flow properties measured help engineers design bins and hoppers that minimize flow problems like arching, ratholing, and flooding.
• Material Handling System Optimization: Enables the selection of appropriate storage and flow equipment, wall angles, and lining materials tailored to specific bulk solid behaviors.
• Quality Control and Process Safety: Regular testing supports ongoing quality assurance in production environments by detecting variations in material consistency.
• Troubleshooting: Provides actionable data to diagnose and resolve existing flow stoppages or irregularities in powder handling systems.
• Compliance and Specification: Often used as a reference in technical specifications, purchase agreements, and regulatory compliance documentation for powder and bulk solids handling.

Related Standards

Organizations implementing ASTM D6128-22 may find the following referenced standards beneficial:

• ASTM D653 - Terminology Relating to Soil, Rock, and Contained Fluids
• ASTM D2216 - Laboratory Determination of Water (Moisture) Content of Soil and Rock
• ASTM D3740 - Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock
• ASTM D4753 - Guide for Evaluating, Selecting, and Specifying Balances and Standard Masses
• ASTM D6026 - Use of Significant Digits and Data Records in Geotechnical Data
• ASTM E177 - Use of the Terms Precision and Bias in ASTM Test Methods
• ASTM E691 - Conducting Interlaboratory Studies to Determine the Precision of a Test Method

Conclusion

ASTM D6128-22 serves as a crucial framework for the assessment of bulk solids flow characteristics using the Jenike Shear Tester. By enabling accurate measurement and interpretation of powder flow properties, this standard promotes safer, more efficient, and more predictable material handling across a wide range of bulk solids industries. For organizations dealing with bulk storage or powder flow, rigorous application of this standard supports robust process design and operational reliability.