MATERIAL DATA SHEET

Circular Hollow Sections (CHS), Grade 350, various sizes

Ferrous Structural
mineral › Metallic › Ferrous Structural
structural-steelchsgrade-350as1163cold-formedhollow-sectioncircularerwaustralian-standard
ATLAS CODE
MIN-MET-FER-008
Circular Hollow Sections (CHS), Grade 350, various sizes
Category mineral
Material Family Metallic
Regulatory Status Non-combustible
Density
7850 kg/m³
Carbon (A1-A5)
1.74 kgCO₂e
Fire Class
Non-combustible
Lifespan
50-100 yrs
Description

CHS Grade 350 steel sections are high-strength, cold-formed circular hollow sections offering excellent structural efficiency with a minimum yield strength of 350 MPa. Manufactured through electric resistance welding (ERW) process, these sections provide superior torsional stiffness, uniform stress distribution, and aesthetic appeal for exposed structural applications. Compliant with AS/NZS 1163:2016 Grade C350L0, they feature guaranteed impact properties at 0°C and are suitable for welding to AS/NZS 1554.1.

Primary Sectors
[Transport & Infrastructure][Industrial]
Typical Uses
  • Structural columns and compression members
  • Architectural exposed structural steel (AESS)
  • Bridge construction and infrastructure
  • High-rise building frames
  • Transmission towers and poles
  • Stadium and arena structures
  • Industrial frameworks and supports
  • Marine structures and offshore platforms
  • Agricultural buildings and equipment
  • Mining infrastructure
  • Temporary structures and scaffolding
  • Cyclone-resistant construction
Recycled Content 25
Renewable Content 0
Recyclability 100
Embodied Carbon 1.74 kgCO₂e
Embodied Energy 20.1 MJ/kg
EPD Available Yes
Advantages
High strength-to-weight ratio (350 MPa minimum yield)Excellent torsional stiffness and resistanceUniform stress distribution in all directionsSuperior aesthetic appeal for exposed applicationsGood weldability with appropriate proceduresAvailable with various protective coatingsComplies with Australian Standards AS/NZS 1163Suitable for all climate zones in Australia100% recyclable at end of lifeProven performance in extreme weather eventsReadily available from Australian suppliersCompatible with standard connection systems
Cautions
Requires fire protection for rated assembliesSusceptible to corrosion without protective coatingHigher initial cost than timber alternativesThermal bridging considerations in building envelopeSkilled labour required for welding and fabricationTransportation limitations for large diametersEmbodied carbon considerations (1.74 tCO₂e/t)Limited availability in remote areas
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TECHNICAL DATA: PERFORMANCE PROPERTIES MIN-MET-FER-008
Density (Dry) 7850 kg/m³
Specific Gravity 7.85
Porosity 0 %
Water Absorption 0 %
Hardness 150
Surface Roughness 6.3 μm
UV Resistance High
Chemical Resistance Moderate
pH Tolerance 4-10
Compressive Strength 350 MPa
Tensile Strength 430 MPa
Flexural Strength 350 MPa
Shear Strength 200 MPa
Elastic Modulus 200000 GPa
Yield Strength 350 MPa
Impact Resistance 27 J/m
Bearing Capacity 525 kN/m²
Poisson's Ratio 0.3
Creep Resistance Excellent
Abrasion Resistance High
Thermal Conductivity 50 W/mK
Thermal Resistance 0.02 m²K/W
Specific Heat Capacity 440 J/kgK
Thermal Expansion 11.7 μm/m·K
Melting Point 1450 °C
Noise Reduction Coeff. (NRC) 0.05
Optical
Light Transmittance 0 %
Light Reflectance (LRV) 35 %

CHS technology evolved from early wrought iron pipes in the 1800s to modern high-strength steel sections. The development of electric resistance welding (ERW) in the 1920s enabled mass production of consistent quality hollow sections. AS/NZS 1163 was first published in 1991, harmonising Australian and New Zealand standards. The introduction of Grade 350 provided an optimal balance between the lower Grade 250 and higher Grade 450, becoming the most widely specified grade for structural applications in Australia. Continuous improvements in steel making and coating technologies have enhanced durability and sustainability, with modern CHS incorporating up to 25% recycled content and achieving design lives exceeding 50 years with appropriate protection systems.

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SAFETY, ECOLOGY & INSTALLATION MIN-MET-FER-008
Flame Spread Index 0
Smoke Developed Index 0
Combustibility Class Non-combustible
Fire Resistance Rating 0-120 minutes hours
Heat Release Rate 0 kW/m²
Toxicity of Combustion None
Embodied Carbon (A1-A3) 1.74 kgCO₂e/kg
Embodied Energy 20.1 MJ/kg
Water Footprint 64 L/kg
EPD Available Yes
Recycled Content 25%
Renewable Content 0%
LEED Points 2
Circular Economy Score 9 /100
VOC Emissions 0 g/L
Skill Level Qualified tradesperson
Crew Size 2
Installation Time 4-8 sections/day hr/m²
Curing Time 0 hours
Setting Time 0 min
Temperature Range -10 to 40 °C
Humidity Range 0-95 %
Required Tools
MIG/TIG welding equipmentAngle grinders and cutting toolsMagnetic drilling equipmentLifting equipment (crane/hoist)Measuring and marking toolsPersonal protective equipmentWelding screens and ventilation
Certifications Required
AS/NZS 1554.1 welding qualificationWhite Card (construction induction)Working at Heights certification (if applicable)Crane/dogman licence (for large sections)
Weather Limitations
No welding in rain or high windsTemperature limits for welding: -10°C to 40°CSurface must be dry for welding
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COMMERCIAL, LOGISTICS & REGULATORY MIN-MET-FER-008
Material Cost $1200-$2000
Installation Cost $80-$150
Annual Maintenance $5-$20
Lifecycle Cost (50yr) $50-$100
Market Availability Readily available
Lead Time 1-4 weeks weeks
Design Life 50-100 years
Warranty Period 10-25 years
Maintenance Interval 5-10 months
Service Temp Range -40 to 400 °C
Freeze/Thaw Resistance Excellent
Dimensional Stability Excellent
Certifications Held
AS/NZS 1163:2016 - Structural steel hollow sectionsAS/NZS 1554.1 - Structural steel weldingAS 4100:2020 - Steel structuresAS/NZS 4680 - Hot dip galvanized coatingsAS/NZS 4792 - Delivery requirementsISO 14001 - Environmental managementEPD to EN 15804 availableGreen Star compliantNo health hazards in serviceSafe Work Australia compliant
Fire Code Compliance
AS 1530.4 - Fire-resistance testsAS 4100 - Steel structures fire design
Standards Compliance
NCC 2022 Volume One & TwoNCC Section B - StructureNCC Section C - Fire ResistanceEquivalent to ASTM A500 Grade BISO 14713 - Zinc coatingsISO 1461 - Hot dip galvanized coatingsComparable to EN 10219 S355J2H

DISCLAIMER: This specification document is generated from the CLAD Materials Atlas Database. Information is for general guidance only and does not constitute professional engineering advice. Values are typical and may vary by batch, manufacturer, and production run. Verify suitability for specific project applications independently.

ID: MIN-MET-FER-008 Schema: v3.0
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