Green Sand Control Equipment – Hot Compression Strength

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Green Sand Control Equipment – Hot Compression Strength Scott M. Strobl Simpson Technologies Corporation

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

Introduction • Are there methods that can better quantify molding sand properties to assist in the preparation of quality molds and defect free castings? • Standard green sand test are within specifications, yet we experience sand related problems. • Search for an illusive sand property – Hot compression strength (elevated temperatures)

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

Agenda • High temperature compression strength test – Application to casting defects – Discuss test procedure and instrument – Review strength-deformation plot – Review some sand and process variables that can influence hot compression strength – Case study – hot compression strength • Muller / Mixer sand comparison – HCS and GCS AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

AFS Core and Mold Process Control • Elevated temperature sand properties – hot compressive strength - “Hot strength is more of a measure of the nature and quality of the clay present than any other factor.”

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

AFS – Casting Defects Hand Book References to molding sand strength and deformation

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

Casting Defects • • • • •

Sand inclusions Swells Mold erosion Expansion defects Broken or cracked castings – Collapsibility

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

High Temperature Compression and Deformation Instrument

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

Sample Preparation

2 in

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

Hot Compression and Deformation Test Procedure

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

Strength-Deformation Plot of a Molding Sand psi

Strength

Deformation

132.0

2.62

psi

% % def.

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

Sand/process variables that can influence HCS • Clay Type – Sodium bentonite – Calcium bentonite

• MB Clay • Mulling – Sand preparation process

• Moisture • Compactability • Mold hardness

• • • • • •

Temperature AFS clay Carbon additives Cellulose additives Cereal additives Others

Influence can change with testing temperature AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA

For additional information, please contact: • • • • •

Scott Strobl Simpson Technologies Corporation 751 Shoreline Drive, Aurora IL 60504 (630) 978 - 0044 [email protected]

AFS Sand Casting Conference October 20-22, 2014 – Indianapolis, IN USA