✓ 100% Real Job Site Archive (2026-2027) ✓ Full-Immersion Hot-Dip Galvanized ISO 1461 ✓ CNC Tube Cold Bending & Jigs ✓ 40ft High Cube Container Ocean QC

Real Factory Fabrication, Hot-Dip Galvanizing & Verified Global Projects

Direct verification from our active manufacturing archives. Inspect real fabrication jigs, robotic welding lines, molten zinc galvanizing tanks, container loading bracing, and authenticated overseas field installations across North America, Europe, and Australia.

01 · Precision Fabrication & Heavy Truss Assembly Flow

From raw Q235B/Q355B high-frequency welded steel tubes to CNC cold curve bending and rigid web member jigging.

  • 01

    CNC Laser & Saw Tube Cutting

    Precise miter cuts and saddle-joint copes with ±0.5mm tolerance, ensuring gapless fit-up for automatic welding seams.

  • 02

    Three-Dimensional Cold Bending

    Multi-roller hydraulic bending conforming exactly to engineered arch curves without chord tube cross-section deformation.

  • 03

    Heavy Jig Positioning & Tack Welding

    Precision full-scale steel jigs anchor top and bottom chords while continuous tubular web members are clamped in place.

  • 04

    CO2 / Argon Shielded Solid Arc Welding

    Full penetration fillet welds on structural joints, ultrasonically inspected to withstand dynamic cyclic wind gusts.

Active Heavy Welding Workshop and Modular Jigs
Step 01 · Laser & Saw Bay

CNC Tube Cutting & Preparation Bay

High-capacity cold saw and tube cutting center cutting structural chords with smooth beveled edges ready for full weld penetration.

Q235B / Q355B ±0.5mm Cut
Spanbest Continuous Fabrication Bay
Step 02 · Truss Jig Line

Heavy Steel Truss Jig Assembly

Full-scale floor jig where circular chord tubes are hydraulically clamped to maintain precise radius curvature during continuous welding.

Rigid Ground Jig Dual Chord
Welded Arch Frame Structural Inspection
Step 03 · Cold Curve Bending

3-Roller Hydraulic Arch Bending

Dedicated heavy tube roller cold-bending round and rectangular hollow sections without wrinkling inner walls or flattening outer curves.

Multi-Radius Smooth Curve
Pre-Assembly of Interlocking Arch Connections
Step 04 · Pre-Assembly QC

Arch Truss Segment Trial Fit-Up

Pre-assembly inspection of curved double-truss ribs verifying sleeve connection alignment and bolt-hole spacing before surface treatment.

100% Pre-Fitted Bolt Hole Match

02 · Hot-Dip Galvanizing Process & Anti-Corrosion Standards

Complete metallurgical bonding under 450°C molten zinc, meeting ISO 1461 / ASTM A123 standards for a 25-year maintenance-free lifespan.

Structural Arch Chords Freshly Lifted from Molten Zinc Tank
Zinc Kettle Extraction

Molten Zinc Bath Extraction

Tubular trusses slowly withdrawn from 450°C molten pure zinc, ensuring even drainage and continuous internal & external metallurgical bonding.

Hot-Dip Galvanized Truss Chords Staging in Cooling Bay
Cooling & Passivation

Quench Tank & Cooling Staging

Water-quenched and chemical passivated batches forming a protective oxide skin that prevents atmospheric white rust during maritime shipping.

Batch Hot-Dip Galvanized Arch Frame Bundles
Zinc Coating Inspection

Finished Galvanized Truss Bundles

Uniform silver-gray crystalline spangle across all structural members, providing sacrificial cathodic protection even if scratched on-site.

Container Mounting Clamps and Hardware Galvanizing QC
Hardware Thickness ≥85μm

Brackets & Base Clamps QC

Every heavy container clamp and structural base bracket tested with magnetic elcometers to ensure zinc coating exceeds 85 μm - 120 μm.

5-Stage Immersion Metallurgy Guarantee:
1. Degreasing & Acid Pickling: Immersed in hydrochloric acid tanks to completely strip scale, oil, and rust down to pure parent steel.
2. Flux Solution Pre-Treatment: Zinc ammonium chloride bath activates metal surface and prevents flash oxidation before dipping.
3. 450°C Molten Zinc Immersion: Pure zinc reacts with iron to form four distinct metallurgical alloy layers (Gamma, Delta, Zeta, and Eta).
4. Quenching & Passivation: Water bath cooling and chromate/phosphate passivation seal surface pores against white rust formation.
5. Magnetic Gauge Testing: Calibrated elcometer verification ensuring minimum average thickness ≥ 85 μm - 120 μm (25-year anti-rust warranty).

03 · Ocean Freight Packaging & High-Security Container Loading

Proven export packing methods preventing cargo shifting, mechanical chafing, or moisture damage across 30+ day ocean voyages.

In-Container Heavy Steel Bundles Forklift Loading
Ocean Stowing Step 01

Forklift Inside 40HQ High Cube

Pre-bundled curved arch trusses staged lengthwise with custom wooden skids, optimizing payload volume and weight balance.

Steel Palletized Hardware and Winch Crate
Ocean Stowing Step 02

Full-Depth Interlocking Stowing

Truss segments arranged in nested layers to maximize 40ft container cube utilization while preventing transverse movement during rough seas.

Heavy-Duty Nylon Cross Lashing
Ocean Stowing Step 03

Heavy Duty Cross-Belt Lashing

5-ton rated polyester webbing straps cross-anchored to container floor D-rings to withstand rough sea roll and pitch.

Container Door Seal Verification and Customs Inspection
Ocean Stowing Step 04

Container Door Bracing & High-Security Seal

Final doorway vertical and horizontal timber bracing locked into container corner posts, followed by tamper-proof ISO 17712 bolt seals.

04 · Authentic Job Sites & 2D Structural Engineering Blueprints

Unfiltered project photography and structural drawings directly sourced from our client archive.

Featured Project · Mega Clear-Span

21×120m Heavy Industrial Clear-Span Truss Shelter

Direct drawing excerpt: 21x120框架搭建图. A 2,520 m² continuous industrial bulk storage canopy engineered with dual circular-chord tubular space trusses and perimeter concrete stub-wall tie-downs.

✓ Clear Span: 21.00m (68.9 ft) completely unobstructed column-free width
✓ Total Length: 120.00m (393.7 ft) with 24 bays at 5.0m spacing
✓ Wind & Snow: 120 km/h design wind speed · 1.5 kN/m² roof snow load
✓ Fabric Cover: 900g/m² high-tenacity PVDF architectural membrane, B1 fire rated
21x120m Structural Frame Blueprint
20x30m Container Canopy Feedback Photo
USA · Mining Staging

20×30m Container-Mounted Canopy

Field feedback showing double-stacked 40ft containers serving as high sidewalls, creating a 600m² sheltered machinery overhaul workshop.

18x12m Container Shelter Field Feedback
Australia · Civil Contractor

18×12m Rapid-Mount Container Shelter

Installed over twin 40ft sea containers in under 2 days. Provides 216m² dust-tight storage for heavy excavators and dump trucks.

40x20m Heavy Duty Warehouse Shelter
Canada · Sub-Zero Climate

40×20m High Snow Load Warehouse

800m² ground-mounted arched shelter engineered with steep pitch roof lines to shed heavy snowdrifts automatically.

20x75m Port Transit Fabric Canopy
Port Logistics · Bulk Cargo

20×75m Bulk Cargo Transfer Shed

1,500m² continuous sheltered terminal protecting moisture-sensitive grain and fertilizer cargo during barge loading.

Need Custom Dimensions or Structural Calculation Books?

Spanbest provides professional PE-stamped engineering calculation books, customized 2D CAD layouts, and container canopy plans within 24 hours.

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