Hot Rolled H Beam AS/NZS 3678 Grade 350 Universal Column Steel Section Welded Building Frame

This hot-rolled H beam is supplied to AS/NZS 3678 Grade 350 and used as a universal column steel section in welded building frames for Australian and New Zealand projects. The member carries a minimum yield strength of 350 MPa, is delivered with mill test certification per heat number, and can be cut, drilled, and primed to your structural drawing before shipment.

Frames are built from two routes:

1. Hot Rolled Universal Column Section: Suits standard profiles and repeat bays where speed matters.

2. Welded Built-up H Beam: Fabricated from AS/NZS 3678 Grade 350 plate, ideal for non-standard depths, wider flanges, long spans, or heavy loads where a rolled profile would be oversized.
   (Both routes deliver the same 350 MPa minimum yield and can be combined in one frame package.)

Why Grade 350 Matters in Australian/NZ Frames

Grade 350 is the working grade for most portal frame columns, rafters, and mezzanine beams in the region. It offers a practical balance between strength and weldability, so a design can be lighter without losing load capacity.

The grade is verified per heat number rather than per shipment, meaning the chemistry and mechanical properties behind the 350 MPa figure can be traced back through the mill certificate for each member. For cold climate sites and dynamic loads, impact-tested options are available: 350L0 (27 J at 0°C) and 350L15 (27 J at -15°C).

Material and Mechanical Properties (Core Specs)

Section and Detail Options

• Custom Depth & Width: Selected to suit span and load, not limited to a standard catalogue.

• Cut to Order: Length matched to the project cutting list, no fixed stock length forced on the design.

• Edges: Supplied as mill edge or sheared edge.

• Drilling: Holes for base plates, splices, and connections drilled to drawing.

• Welded Details: Stiffener plates, end plates, gussets, and cleats welded to the column section.

• Surface Treatment: Supplied as rolled, shot blasted, or shop primed. Hot-dip galvanizing coordinated on request.

Fabrication and Quality Control

• Incoming plate matched against AS/NZS 3678 Grade 350 mill certificate before cutting.

• CNC cutting of flange and web components to the structural cutting list.

• Submerged arc and MIG welding of built-up H beams and welded column sections.

• Weld procedure qualification and welder qualification records kept on file.

• Straightness, flange squareness, and web alignment checked against AS/NZS 3678 tolerance.

• Dimensional and visual report issued before shipment (third-party inspection welcome).

• Every member match-marked and numbered for site erection sequence.

Typical Applications

• Portal frame columns and rafters for industrial sheds, warehouses, and workshops.

• Multi-storey steel building frames and mezzanine floor beams.

• Commercial steel buildings, showrooms, and aircraft hangar structures.

• Pre-engineered building (PEB) primary framing members.

• Conveyor gantries, mining plant support structures, and equipment skids.

• Bridge girders and heavy fabricated steel structure assemblies.

• Replacement columns and transfer beams for existing steel frames.

Packing and Delivery

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

• Timber dunnage between layers to protect primed surfaces.

• Steel strapping and edge protection for container loading.

• Flat rack and break-bulk options for members beyond container limits.

• Loading plan and packing list issued with the shipping documents.

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Buyer Questions (FAQ)

Q: Is AS/NZS 3678 the correct standard for a hot-rolled H beam?
A: AS/NZS 3678 covers hot-rolled structural plates. Welded built-up H beams are fabricated from this Grade 350 plate, while hot-rolled universal columns are supplied to the AS/NZS 3679.1 Grade 350 equivalent. Both routes give a 350 MPa minimum yield 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. Grade 350L0 adds Charpy impact testing of 27 J at 0°C. Grade 350L15 adds 27 J impact testing at -15°C for colder service conditions.

Q: Should the frame use hot-rolled sections or welded built-up beams?
A: Hot-rolled universal columns are economical for standard profiles and fast delivery. Welded built-up H beams from Grade 350 plate offer more flexibility for non-standard depths, wide flanges, long spans, and heavy loads, making stiffener/connection integration easier.

Q: Can the whole building frame be supplied, not only the column?
A: Yes. Columns, rafters, purlins, bracing, base plates, and anchor bolts can be fabricated and match-marked as one complete welded building frame package.

About Us & Get a Quote

Hangzhou FAMOUS Steel Engineering Co., Ltd. (FASECbuildings) is a professional steel structure manufacturer with over 20 years of experience serving global projects, including the Australian and New Zealand markets. We hold ISO 9001 and CE (EN 1090) certifications, ensuring world-class fabrication quality.

📩 Request a Section Schedule Today! Send your structural drawings or cutting list, and our engineering team will reply with a tailored section schedule, fabrication scope, and competitive delivery plan for your AS/NZS 3678 Grade 350 requirements.

🌐 Websites: www.famoussteel.com | www.steelfabricat.com | www.structural-steelbuilding.com