Shijiazhuang Zhengzhong Technology Co.,Ltd(Center Enamel) designs and fabricates API 650 compliant welded steel tanks for bulk oil storage, midstream terminals, and refinery applications. Engineered with ASTM A516 Grade 70 carbon steel and automated Submerged Arc Welding (SAW), our tanks support capacities from 500 m3 to 50,000 m3+. We provide integrated solutions for Internal Floating Roofs (IFR), API 2000 venting compliance, and NFPA-standard fire suppression, ensuring a 30-year service life in aggressive hydrocarbon environments.
Parameter | Technical Specification | Operational Value |
Primary Standard | API 650 / API 620 | Verified for global refinery and SPR use. |
Material Grade | Normalized ASTM A516-70 | Prevents Hydrogen-Induced Cracking (HIC). |
Welding Method | Automated SAW | Fused joints exceed base metal tensile strength. |
NDT Protocol | 100% RT (T-Joints) + Vacuum Box | Guaranteed zero-leakage containment. |
VOC Control | Mechanical Shoe Seal IFR | 99% reduction in vapor loss and emissions. |
Generic "carbon steel" is a weak authority signal. We define reliability through specific material science:
● High-Yield Shell Plates: We utilize pressure-vessel quality ASTM A516 Grade 70 or Q345R steel, offering superior notch toughness for large-scale reservoirs.
● HIC Resistance: For "sour" crude (high H2S), our steel undergoes Normalized heat treatment. This refines the grain structure to resist Hydrogen-Induced Cracking (HIC), preventing internal blistering and structural fatigue.
The integrity of an oil tank is verified by its fused joints. We provide verifiable proof of monolithic structural integrity:
● 100% Radiographic Testing (RT): Conducted on all critical vertical seams and "T-joints" to verify a zero-porosity internal structure.
● Vacuum Box Testing: Every inch of the floor-plate lap welds is tested at -35 kPa to guarantee the primary containment barrier is 100% leak-proof.
● Surface Prep (SA 2.5): Internal surfaces undergo Near-White Metal Sandblasting to ensure maximum adhesion for Glass-Flake Reinforced (GFR) Epoxy linings, protecting against corrosive water-bottoms.
● Foundation Engineering: We design Reinforced Concrete Ring Beams with Oiled Sand Cushions. This prevents differential settlement and acts as a corrosion barrier for the tank floor's underside.
● API 2000 Venting: All tanks feature Pressure/Vacuum Relief Valves (PVRV) compliant with API 2000, preventing catastrophic rupture during thermal expansion or rapid pumping.
● Lightning Protection: We utilize Stainless Steel Shunts to electrically bond floating roofs to the shell, mitigating static ignition risks in the rim seal zone.
● Aluminum Geodesic Domes: Our clear-span dome roofs provide superior load-bearing capability and corrosion resistance, eliminating the need for internal support columns.
● VOC Reduction: By pairing our welded tanks with Internal Floating Roofs (IFR) and mechanical shoe seals, we achieve the 99% emission reduction benchmark required by modern ESG mandates.
● Q: What is the maximum diameter for your API 650 welded tanks?
○ A: We provide field-welded solutions for diameters exceeding 60 meters, utilizing Finite Element Analysis (FEA) to ensure stability under maximum hydrostatic loads.
● Q: Do your oil tanks meet NFPA 11 fire protection standards?
○ A: Yes. Our designs include pre-engineered attachments for foam chambers and firewater cooling rings in accordance with NFPA 11 and NFPA 15.
● Q: Can you convert an existing fixed-roof tank to a floating-roof tank?
○ A: Yes. We offer retrofitting using Aluminum Geodesic Domes and internal floating decks to upgrade assets for 99% VOC recovery.
