AS/NZS 3678 Grade 350 Hot Rolled H Beam Universal Column Section Welded Steel Structure Member

This AS/NZS 3678 Grade 350 structural steel member is built specifically for Australian and New Zealand projects. Each universal column section delivers a minimum yield strength of 350 MPa, full mill test traceability per heat number, and fabrication-ready surfaces.

We offer a dual supply route to match your engineering design:

1. Welded Built-up H Beam: Fabricated from Grade 350 structural steel plate, allowing us to control flange/web thickness, weld quality, and hole positions.

2. Hot Rolled Universal Column: Equivalents to AS/NZS 3679.1 Grade 350 are available on request where a rolled profile is specified.

Key Features

• 350 MPa Yield Strength: AS/NZS 3678 Grade 350 structural steel with 450 MPa tensile strength for heavy-load columns and rafters.

• Dual Supply Route: Choose between hot-rolled UC sections or welded built-up H beams from Grade 350 plate.

• In-House Fabrication: Cutting, drilling, coping, notching, welding, and shop-priming are all completed before shipment.

• Impact Tested Options: Grade 350L0 and Grade 350L15 are available for cold climate and dynamic load applications.

• Full Traceability: Mill Test Certificates (MTC) issued per heat number with every delivery.

• Dimensional Control: Straightness, flange squareness, and web alignment are verified against AS/NZS 3678 tolerances.

Technical Specifications

Fabrication Process

1. Plate Selection: AS/NZS 3678 Grade 350 plate verified against mill certificate and heat number.

2. CNC Cutting: Flange and web components cut to the structural cutting list with recorded dimensions.

3. Welding: Submerged arc and MIG welding of built-up H beams and welded column sections.

4. Drilling & Details: Base plate, splice, and connection holes drilled; stiffeners, end plates, and cleats welded.

5. Surface Treatment: Shot blasting and shop primer (with hot-dip galvanizing coordination on request).

6. Marking & Packing: Every member marked and match-numbered for site erection, then bundled for export.

Typical Applications

• Industrial Sheds: Portal frame columns and rafters for warehouses and factory buildings.

• Multi-Storey Frames: Primary columns and mezzanine floor beams for steel building frames.

• Commercial Buildings: Showrooms, aircraft hangars, and pre-engineered building framing.

• Mining & Plant: Conveyor gantries, equipment skids, and heavy support structures.

• Bridges: Girders and heavy fabricated steel structure assemblies.

• Structural Upgrades: Replacement columns and transfer beams for existing steel frames.

Quality Control

• Incoming plate verified against AS/NZS 3678 Grade 350 mill certificates.

• Chemical composition and mechanical properties confirmed per heat number.

• Weld procedure qualification and welder qualification records maintained.

• Dimensional inspection of flange width, web thickness, straightness, and hole position.

• Visual and dimensional report issued before shipment; third-party inspection welcome.

Packing and Delivery

• Members bundled by section type and marked with project item numbers.

• Timber dunnage placed between layers to protect primed surfaces.

• Steel strapping and edge protection for container loading.

• Break-bulk and flat-rack options available for long structural steel members.

• Loading plan and packing list issued with shipping documents.

Frequently Asked Questions (FAQ)

Q: Is AS/NZS 3678 the correct standard for H beams?
A: AS/NZS 3678 covers hot-rolled structural steel plates, floorplates, and slabs. Our H beams are either fabricated from AS/NZS 3678 Grade 350 plate into welded built-up sections or supplied as hot-rolled universal column sections to AS/NZS 3679.1 Grade 350. Both routes deliver a 350 MPa minimum yield and are accepted on Australian and New Zealand projects.

Q: What is the difference between Grade 350, 350L0, and 350L15?
A: Grade 350 is the base structural grade with 350 MPa minimum yield. Grade 350L0 adds Charpy impact testing of 27 J at 0°C, while Grade 350L15 adds 27 J impact testing at -15°C for colder service conditions.

Q: Should I choose a welded H beam or a hot rolled universal beam?
A: A hot-rolled universal column section is economical for standard profiles. A welded built-up H beam from Grade 350 plate is more flexible for non-standard flange/web combinations, long spans, heavy loads, and makes stiffener/connection integration easier.

Q: Can the section be cut, drilled, and primed to my drawing?
A: Yes. We fabricate to the project cutting list and structural drawings, including hole drilling, coping, end plate welding, and shop priming, then mark each member for site erection.

Q: Do you provide mill test certificates?
A: Every shipment includes mill test certificates per heat number covering chemical composition and mechanical properties, with third-party inspection available on request.

📩 Need a Quotation for Your H Beam Package?

Send your structural drawings or cutting list, and we will reply with a section schedule, fabrication scope, and delivery plan.

Contact Us Today to Start Your Project.