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Heavy Structural Steel & API 650 Mega Tank Modules for World-Scale Refinery & Petrochemical Complex in Lekki, Nigeria
Fully compliant with American Petroleum Institute (API 650) tank specifications and AWS D1.1 structural welding codes, satisfying the highest tier of international oil & gas specifications in West Africa.
Project Overview
Located in the Lekki Free Trade Zone along the Gulf of Guinea, this world-scale downstream energy project represents the largest single-train petroleum refinery and tank farm complex in Africa. The coastal, tropical rainforest climate poses extreme engineering challenges: constant high humidity, heavy marine salt spray (ISO 12944 C5-M atmospheric corrosivity), and unforgiving subsoil settlement in delta coastal plains. Furthermore, international oil majors and EPC contractors enforce uncompromising third-party QA/QC surveillance (conducted by BV / SGS / DNV) under strict API 650, ASME Section IX, and AWS D1.1 standards.
Facing severe criteria where numerous international fabricators faltered during stringent 100% full-penetration radiographic (RT) and ultrasonic (UT) testing on ultra-thick plate weldments, Shijie Heavy Industry successfully delivered critical heavy-duty box columns, pipe rack steel structures, and prefabricated API 650 tank shell plates. Our automated submerged arc welding (SAW) and flux-cored arc welding (FCAW) achieved a 100% first-pass NDT rate with zero slag or pore defects. Backed by trace-verifiable EN 10204 3.1 Material Test Reports (MTRs) and marine-grade anti-corrosion coating systems, Shijie solidified its reputation as an elite heavy industrial fabricator for Africa's most demanding mega-projects.
| Location | Lekki FTZ, Lagos State, Nigeria (Gulf of Guinea) |
| Industry | Integrated Oil Refinery & Large-Scale Tank Farm Terminal |
| Design Codes | API 650, ASME Sec. VIII/IX, AWS D1.1, ISO 12944 |
| Key Deliverables | Massive Box Columns, Heavy Pipe Racks & API 650 Tank Shells |
| Coating Spec | ISO 12944 C5-M (Marine High Durability System) |
| Welding Spec | 100% Complete Joint Penetration (CJP) welds with low heat input |
| Dual NDT | 100% UT + RT / PAUT inspection per ASME/AWS criteria |
| Documentation | Full EN 10204 3.1 MTRs with traceability heat mapping |
| Outcome | 100% First-Pass Acceptance (Zero on-site repair rate) |
| Third-Party TPI | Verified by Tier-1 International TPI (BV / SGS / DNV) |
API 650 & Marine Petrochemical Compliance
Fully compliant with American Petroleum Institute (API 650) tank specifications and AWS D1.1 structural welding codes, satisfying the highest tier of international oil & gas specifications in West Africa.
100% First-Pass Dual NDT
Utilizing automated submerged arc welding (SAW) and certified international welding engineers (IWE), achieving zero internal voids, slag, or micro-cracks under dual Radiographic (RT) and Ultrasonic (UT) examinations.
Heavy-Gauge Plate Distortion Control
Mastered symmetrical alternating welding and post-weld heat treatment (PWHT) procedures, perfectly controlling residual stress and geometric tolerances on massive box columns and tank curved plates.
Tropical Marine C5-M Anti-Corrosion
Applied high-build inorganic zinc-rich + epoxy micaceous iron oxide + aliphatic polyurethane systems under blast grade Sa 2.5, guaranteeing decades of structural integrity against coastal salt spray and high tropical humidity.
Turning Site Challenges into Engineered Certainty
Proven technical interventions to keep your project on spec, on budget, and on schedule
Coastal marine environment with extreme humidity and high ambient salinity accelerates pitting and galvanic corrosion.
Executed high-performance ISO 12944 C5-M coating specs (total dry film thickness ≥ 320 µm) using robotic airless spraying, with rounded edge radiusing (R ≥ 2mm) to guarantee continuous film integrity.
Thick-plate box columns and tank shell joints face acute hot/cold crack risks under rigorous RT/UT criteria.
Deployed dual-torch submerged arc welding with precise interpass temperature control (150°C-200°C) and certified low-hydrogen consumables, backed by 100% Phased Array Ultrasonic Testing (PAUT) verification.
Highly complex customs and logistical scrutiny for project material clearance and provenance within Nigerian Free Zones.
Supplied dual-authenticated EN 10204 3.1 / 3.2 inspection certificates directly traced to premier steel mills, with hard-stamped heat numbers and QR-linked digital dossiers for instant verification.
Any QA/QC director who has overseen mega-refinery and tank farm constructions in Nigeria will affirm that executing projects here means confronting the twin hurdles of extreme marine-tropical corrosion and the industry’s most unforgiving third-party inspection audits. In our coastal site along the Gulf of Guinea, there is zero tolerance for weld imperfections or substandard coatings—salt spray will expose any defect within weeks.
We required massive box columns and critical heavy structures for the main processing units and tank farm connectivity, with strict 100% CJP full-penetration welding governed by API and AWS standards. Shijie Heavy Industry exceeded our most demanding criteria. Their welds cleared mandatory 100% UT and RT tests on the very first attempt without a single defect—a feat that many seasoned global suppliers fail to deliver in heavy-plate fabrication. Moreover, their EN 10204 3.1 material test certificates and C5-M coating quality inspection files passed through international TPI auditors seamlessly. Shijie demonstrates true world-class mastery in heavy petrochemical steel engineering.
Products Used in Project
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Why Global Contractors Choose SynJect
Predictable delivery, certified compliance, and direct engineering support for zero-risk execution
Pre-assembled in our factory and 3D-nested for containers to cut ocean freight and site delays
Fabricated strictly to CE EN 1090-1, AISC, and ISO 9001 / 14001 / 45001 with full NDT traceability
Work directly with senior structural engineers from Tekla 3D modeling to on-site erection
Frequently Asked Questions
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Steel Weight Savings
1:1 Tekla 3D modeling optimizes beam-column ratios to eliminate redundant material costs.
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Checked against EN 1090 and local wind/seismic loads.
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