Fabrication of storage tanks for petroleum, chemical, and water storage applications. We build API 650, API 620, and EN 14015 tanks with capacities from 100m³ to 100,000m³, including floating roof, fixed roof, and pressure tank designs.
30,000 T/Year Capacity
Plate up to 200mm
AWS D1.1 / EN 1090
Full NDT Testing
Leading Top Union delivers fabricated storage tanks engineered to API 650, API 620, and EN 14015 standards, covering diameters from 3 m to 80 m and capacities up to 100,000 m³. In-house plate rolling and forming capabilities handle shell thicknesses from 6 mm to 50 mm, using carbon steel, stainless steel, duplex, and clad materials. Each tank is designed for specific service conditions, including atmospheric and low-pressure storage of crude oil, refined products, chemicals, and water. All nozzles, manholes, and appurtenances are integrated during fabrication, reducing field work and ensuring dimensional accuracy within ±2 mm on shell plate alignment per AWS D1.1 structural welding criteria.
The fabrication process begins with material traceability per EN 10204 Type 3.1 or 3.2 certifications, followed by CNC cutting and edge preparation to achieve weld bevel tolerances of ±0.5 mm. Shell plates are cold-rolled using 4-roll bending machines capable of forming plates up to 50 mm thick with a diameter tolerance of ±3 mm on circumference. Longitudinal and circumferential seams are welded using submerged arc welding (SAW) and gas metal arc welding (GMAW) processes, with weld metal impact testing at -20°C per ISO 148-1 for low-temperature service. All welds undergo 100% visual inspection and non-destructive testing (NDT) including radiographic (RT) and ultrasonic (UT) examination per ASME Section V.
Multiple roof configurations are offered to match operational requirements. Floating roofs are fabricated with double-deck or pontoon designs per API 650 Appendix H, with rim seal systems meeting EPA 40 CFR Part 60 Subpart Kb for vapor emission control. Fixed cone roofs are constructed with a minimum slope of 1:6 per API 650 Section 5.10, using self-supporting or column-supported structures. Dome and geodesic roofs are formed from aluminum or steel panels, spanning up to 80 m without internal supports, designed per API 650 Appendix G or EN 14015 Section 8. Field erection supervision is provided on-site for tank assembly, hydrostatic testing, and vacuum box testing of bottom plates, ensuring compliance with project specifications and local regulations.
In the oil and gas sector, storage tanks serve as critical infrastructure for upstream, midstream, and downstream operations. For crude oil terminals, floating roof tanks are fabricated with capacities up to 100,000 m³, designed for a maximum working pressure of 2.5 kPa and a design temperature range of -20°C to 90°C per API 650. These tanks incorporate aluminum or stainless steel floating roofs with foam-filled pontoons for buoyancy and corrosion resistance. Fixed cone roof tanks are also supplied for refined products like gasoline, diesel, and jet fuel, with internal cathodic protection systems per NACE SP0169 to prevent bottom plate corrosion in sour service environments.
For petrochemical and chemical processing plants, tanks are engineered to API 620 for low-pressure storage of volatile liquids such as ethylene, propylene, and ammonia. These tanks are designed for internal pressures up to 15 psig (103 kPa) and temperatures from -40°C to 260°C, using materials like 304L or 316L stainless steel for corrosion resistance. Dome roof tanks are ideal for storing sulfuric acid, caustic soda, and other aggressive chemicals, with rubber-lined or glass-reinforced epoxy (GRE) internal coatings applied per SSPC-SP10 near-white blast cleaning standards. Clad plate tanks are also provided for hydrofluoric acid alkylation units, where the Monel or Hastelloy cladding thickness is maintained at a minimum of 3 mm per ASTM B898.
In the power generation industry, tanks support fuel oil storage, demineralized water storage, and fire water systems. For thermal power plants, heavy fuel oil (HFO) tanks are fabricated with steam heating coils and insulation to maintain viscosity at 50°C, with capacities ranging from 5,000 m³ to 30,000 m³. For combined cycle gas turbine (CCGT) plants, condensate storage tanks are supplied with nitrogen blanketing systems to prevent oxygen ingress, designed per ASME BPV Code Section VIII Division 1. Offshore wind farms require ballast water tanks and freshwater storage tanks fabricated from duplex stainless steel (UNS S31803) for corrosion resistance in marine environments, with wall thicknesses optimized for 25-year design life per DNV-OS-C101.
Mining and mineral processing operations rely on these tanks for slurry storage, leach solutions, and process water. For copper and gold heap leaching, large-diameter tanks up to 50 m are fabricated with rubber-lined carbon steel shells to handle acidic solutions with pH levels as low as 1.5. These tanks are designed per EN 14015 with conical bottoms for solids settling, using 12 mm to 25 mm thick plates with internal stiffeners. In the shipbuilding sector, marine storage tanks are supplied for LNG carriers and chemical tankers, fabricated from 9% nickel steel (ASTM A553) or stainless steel, with cryogenic service capability down to -196°C per IGC Code and DNV-GL rules. These tanks meet IMO Type C independent tank requirements for pressure vessels up to 10 bar.
ISO 3834-2 certification for fusion welding of metallic materials ensures consistent quality across all fabrication stages, from material receipt to final inspection. A controlled welding procedure qualification (WPQ) database is maintained covering over 500 procedure qualification records (PQRs) for carbon steel, stainless steel, duplex, and clad materials. Each welder is certified per AWS D1.1 or EN 287-1, with annual performance qualification tests. The in-house NDT laboratory is equipped with digital radiography (DR) systems, phased array ultrasonic testing (PAUT) units, and magnetic particle inspection (MPI) stations, enabling real-time defect detection with a sensitivity of 1.5 mm for planar flaws per ASME Section V Article 4.
A complete turnkey solution is offered including design, fabrication, surface preparation, and field erection supervision. Finite element analysis (FEA) software per ASME Section VIII Division 2 Part 5 is used for stress analysis of tank shells, roofs, and foundations under wind, seismic, and hydrostatic loads. For seismic zones, designs per ASCE 7-16 with response modification factors up to 3.5 for anchored tanks are applied. Surface preparation follows SSPC-SP6 commercial blast cleaning for carbon steel, with epoxy and polyurethane coating systems applied in a climate-controlled shop to achieve dry film thickness (DFT) of 250-400 microns per NACE SP0188. Hydrostatic testing is also provided with water at 1.25 times the design pressure, monitored by calibrated pressure gauges and data loggers.
Global project experience includes delivery to EPC contractors in the Middle East, Southeast Asia, Africa, and South America. For a recent refinery expansion in Saudi Arabia, 12 floating roof tanks were supplied with diameters of 45 m and shell heights of 20 m, fabricated from ASTM A516 Grade 70 carbon steel with a minimum yield strength of 260 MPa. All tanks passed API 650 hydrostatic and vacuum box tests with zero leaks, and field erection was completed within 14 weeks using an on-site supervision team. A 50,000 m³ LNG storage tank was also completed for a petrochemical complex in Indonesia, using 9% nickel steel plates with Charpy V-notch impact energy of 40 J at -196°C per ASTM A553 Type I. Clients benefit from reduced project risk through single-source responsibility, with warranty coverage extending up to 24 months from commissioning.
Custom tank designs are supported for non-standard applications, including double-wall tanks for cryogenic service, insulated tanks for heated storage, and tanks with internal floating covers for vapor recovery. Materials are sourced from approved mills with EN 10204 Type 3.1 certifications, ensuring full traceability from melt to final product. For clad plates, explosion-bonded or roll-bonded materials per ASTM B898 are used, with cladding thickness verified by ultrasonic testing at 100% coverage. Optional features such as vortex breakers, anti-slosh baffles, and internal ladders per API 650 Section 5.8 are also offered. With a production capacity of 15,000 metric tons per year and a dedicated project management team, Leading Top Union delivers storage tanks that meet the most demanding technical and schedule requirements for global energy and industrial projects.
| Capability | Specification |
|---|---|
| Diameter Range | 3 - 80m |
| Capacity | 100 - 100,000 m³ |
| Shell Thickness | 6 - 50mm |
| Standards | API 650, API 620, EN 14015 |
| Materials | Carbon steel, stainless, duplex, clad |
| Roof Types | Floating, fixed cone, dome, geodesic |
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