ASTM-Certified Q355b Steel Truss Structures for Heavy-Duty Factory Roofs and Warehouses

Product Description

At Hangzhou FAMOUS Steel Engineering Co., Ltd. (FASECbuilding), we design and manufacture ASTM-Certified Q355B Steel Truss Structures specifically for heavy-duty factory roofs and warehouses. Our steel truss is a structural system composed of straight steel members connected at nodes to form triangular units, which efficiently transfer loads through axial forces. Thanks to its high strength-to-weight ratio, the truss structure is widely used in large-span, heavy-load industrial projects. All components are factory prefabricated and pre-assembled, ensuring high precision and enabling rapid on-site erection.

Key Features & Advantages
• High Strength-to-Weight Ratio: Q355B steel delivers minimum 355 MPa yield strength, allowing strong load-carrying capacity with reduced steel consumption.
• Large-Span Capability: Suitable for spans from medium to very large without intermediate columns, maximising usable floor space.
• Superior Load-Bearing Performance: Performs exceptionally well under heavy loads, wind, and seismic forces.
• Factory Pre-Assembled: High-precision fabrication under controlled conditions ensures consistent quality and dimensional accuracy.
• Durable & Long Service Life: Anti-corrosion surface treatments ensure long-term performance and durability.
• Excellent Weldability: Q355B offers superior weldability with all common welding methods, often without preheating.
• Flexible Design Options: Various truss types and geometries to meet architectural and functional requirements.

Customization & Engineering Services

We understand that every factory and warehouse has unique structural requirements. That is why we offer full customization and engineering support:

• Tailored Span and Load Design: We calculate the optimal truss configuration based on your roof slope, column spacing, crane load, and local environmental conditions (wind, snow, seismic).
• Section Profile Selection: We help you select the most cost-effective H-sections, steel tubes, angles, or built-up box sections to meet strength and stiffness criteria.
• Connection Optimisation: Our engineers design bolted or welded connections with detailed shop drawings, ensuring ease of erection and structural integrity.
• Value Engineering: We continuously optimise member sizes and node details to reduce steel tonnage and overall project cost without compromising safety.
• Coordination with Other Trades: We provide 3D models and detailed fabrication drawings to facilitate coordination with foundations, cladding, and overhead crane systems.
Our engineering team uses advanced software (e.g., Tekla, STAAD Pro, and AutoCAD) to deliver precise and constructible designs.

Structural Design Options
Our trusses feature a stable triangular lattice structure that provides excellent load distribution and stability. We offer various truss types to meet your specific project requirements, including:

• Roof Truss / Plane Truss / Space Truss
• Warren Truss / Pratt Truss / Howe Truss
• Triangular / Polygonal Truss
The triangular configuration provides excellent load distribution and stability, making it particularly suitable for large-span, heavy-load industrial applications. Compared with solid-web steel beams, steel trusses use sparse web members instead of an integral web, and the members mainly bear axial force, which can save steel and reduce structural weight.

Fabrication Process

At our facility, we follow a rigorous fabrication process to ensure the highest quality:

1.Structural analysis and truss layout design
2.Shop drawing preparation and material confirmation
3.CNC cutting, drilling, and member fabrication
4.Assembly and automatic welding
5.Non-destructive testing (UT / MT)
6.Dimensional inspection and trial assembly
7.Surface treatment (sandblasting, painting, galvanizing)
Our advanced fabrication facilities include CNC cutting, automatic welding, and precision assembly lines.

Quality Control
We implement a strict quality control system throughout the entire production process:

• Full material traceability with Mill Test Certificates (MTC)
• Qualified welders with approved Welding Procedure Specifications (WPS) and Procedure Qualification Records (PQR)
• Dimensional inspection and visual welding inspection
• Optional NDT (UT / MT) for critical joints
• Pre-assembly inspection for key structural modules
• Surface treatment inspection and final packing inspection before shipment
At FASECbuilding, we take pride in every detail to ensure your trusses meet the highest standards.

Specification

Item	Detailed Description
Material & Mechanical Properties	Q355B low-alloy high-strength steel. Yield strength: ≥355 MPa (t≤16mm) / ≥345 MPa (16<t≤40mm). Tensile: 470–630 MPa. Elongation: ≥21%. Impact energy (20°C): ≥34 J (longitudinal). Carbon equivalent (CEV): ≤0.45 to ensure excellent weldability. All MTCs are traceable to heat numbers.
Section & Member Sizing	Customised hot-rolled or fabricated sections: H-beams (up to 900 mm depth), channels, angles, and rectangular tubes. Flange/web thickness can be designed up to 40 mm, with stiffeners at supports and load points. All sections are selected to meet global buckling and local buckling requirements per AISC or EN 1993.
Connection Design & Welding	Welded connections: Full-penetration butt welds for splices, fillet welds for bracing. All welds are AWS D1.1 qualified with prequalified WPS. Bolted connections: High-strength friction-grip bolts (grade 10.9) with slip-critical joints. Shop drawings specify bolt diameters, pitch, edge distances, and torque requirements.
Fabrication Tolerances & Inspection	Length tolerance: ±2 mm per member. Straightness: ≤ L/1000. Angular deviation: ±1° for chord members. Hole alignment: within 1.5 mm. NDT: 100% UT for butt welds and MT for surface cracks on critical joints. Dimensional verification via total station or laser alignment prior to shipment.
Surface Preparation & Coating	Abrasive blast cleaning to Sa2.5 (ISO 8501-1) with surface profile of 50–75 μm. Primer: inorganic zinc-rich (75 μm DFT) or epoxy primer. Topcoat: polyurethane or acrylic (total DFT 120–160 μm) for atmospheric exposure. Hot-dip galvanizing (min. 85 μm) available for aggressive environments. Coating adhesion and thickness are tested with cross-cut and magnetic gauge.
Design Life & Environmental Suitability	Engineered for a 50-year design life under normal industrial atmospheric conditions (C2–C4 corrosivity per ISO 12944). We can adapt coating and steel grades for high-humidity, coastal, or chemical-exposed environments. Seismic design per applicable codes (ASCE 7, EC8) on request.

All parameters are fully adjustable to match your project specifications and local building codes.

Packaging & Shipping

We take great care in packaging and shipping our trusses:

• Packaging: Standard seaworthy export packing with edge protection and moisture-proof coating.
• Transportation: Container or bulk carrier transportation. We use modular packing to optimise container or break-bulk shipment.
• Protection: Protective measures for coated surfaces during transport.
• Identification: Clear identification markings for easy on-site installation.

After-Sales Service
We are committed to supporting you beyond delivery:

• On-site installation guidance or full installation service available.
• 1-year warranty period.
• Professional technical support from design to delivery.
• Responsive after-sales team to address any concerns promptly.
As FASECbuilding, we stand by our products and your satisfaction is our priority.

Company Profile
We are Hangzhou FAMOUS Steel Engineering Co., Ltd. (FASECbuilding), a professional steel structure manufacturer with extensive experience in engineering-oriented steel structure projects.

• Advanced Fabrication Facilities: CNC cutting, automatic welding, and precision assembly lines.
• Strict Quality Control System: Full material traceability, certified welders, and NDT inspection.
• Strong Customization Capability: Customised engineering solutions to reduce weight and cost.
• Global Project Experience: Steel trusses supplied to industrial and infrastructure projects worldwide.
• Stable Production Capacity: Capable of handling medium to large-scale projects.
We look forward to being your trusted partner for your next steel truss project!