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.
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CNC Laser & Saw Tube Cutting
Precise miter cuts and saddle-joint copes with ±0.5mm tolerance, ensuring gapless fit-up for automatic welding seams.
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Three-Dimensional Cold Bending
Multi-roller hydraulic bending conforming exactly to engineered arch curves without chord tube cross-section deformation.
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Heavy Jig Positioning & Tack Welding
Precision full-scale steel jigs anchor top and bottom chords while continuous tubular web members are clamped in place.
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CO2 / Argon Shielded Solid Arc Welding
Full penetration fillet welds on structural joints, ultrasonically inspected to withstand dynamic cyclic wind gusts.
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.
Heavy Steel Truss Jig Assembly
Full-scale floor jig where circular chord tubes are hydraulically clamped to maintain precise radius curvature during continuous welding.
3-Roller Hydraulic Arch Bending
Dedicated heavy tube roller cold-bending round and rectangular hollow sections without wrinkling inner walls or flattening outer curves.
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.
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.
Molten Zinc Bath Extraction
Tubular trusses slowly withdrawn from 450°C molten pure zinc, ensuring even drainage and continuous internal & external metallurgical bonding.
Quench Tank & Cooling Staging
Water-quenched and chemical passivated batches forming a protective oxide skin that prevents atmospheric white rust during maritime shipping.
Finished Galvanized Truss Bundles
Uniform silver-gray crystalline spangle across all structural members, providing sacrificial cathodic protection even if scratched on-site.
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.
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.
Forklift Inside 40HQ High Cube
Pre-bundled curved arch trusses staged lengthwise with custom wooden skids, optimizing payload volume and weight balance.
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 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 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.
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.
20×30m Container-Mounted Canopy
Field feedback showing double-stacked 40ft containers serving as high sidewalls, creating a 600m² sheltered machinery overhaul workshop.
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.
40×20m High Snow Load Warehouse
800m² ground-mounted arched shelter engineered with steep pitch roof lines to shed heavy snowdrifts automatically.
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.