What Type of Steel Plate Is Used for Oil & Gas Storage Tanks?

Introduction

In the oil & gas industry, the structural integrity of storage tanks depends heavily on the quality and specification of the steel plate for tank fabrication. Whether you’re building atmospheric tanks, pressure vessels, LNG terminals, or crude oil reserves, selecting the proper material is a technical and safety-critical decision.

This article breaks down the most appropriate carbon steel and pressure vessel steel grades, their material characteristics, standards, and project-specific considerations — to help engineers and EPC contractors make confident, informed material decisions.

Why Steel Plate Selection Is Critical in Tank Fabrication？

Storage tanks in oil & gas applications are exposed to high internal pressure, aggressive chemicals, and fluctuating temperatures. A material failure can cause environmental contamination, financial loss, or catastrophic accidents.

That’s why choosing the right steel plate for the oil & gas industry, especially for storage tank and pressure vessel fabrication, is a critical engineering and safety decision. EPC engineers typically specify materials that comply with standards such as ASME Section VIII, EN 10028, and API 650/620 to ensure regulatory compliance and long-term operational safety.

In practical applications, common tank plate material grades include ASTM A516 Grade 70 for refinery tanks and carbon steel plates for fuel and oil storage. For low-temperature applications such as LNG tanks, steel sheet for the oil & gas industry must provide enhanced impact resistance and cryogenic toughness to ensure long-term reliability.

In some EPC documentation, the term steel sheet for the oil & gas industry is used broadly to describe plate materials supplied in thinner gauges, typically for auxiliary tanks, linings, or non-pressure applications. In such cases, impact resistance and low-temperature toughness remain important considerations depending on service conditions.

What Is the Typical Tank Plate Material for Oil & Gas Storage Tanks?

In oil & gas projects, tank plate material selection is primarily driven by design pressure, operating temperature, stored media, and applicable construction codes such as API 650, API 620, and ASME Section VIII.

For atmospheric and low-pressure storage tanks, carbon steel plates like ASTM A516 Grade 70 and EN 10028 P355GH are commonly specified due to their balanced strength, weldability, and cost efficiency.

In higher-pressure or thicker-wall tank applications, quenched and tempered steels such as ASTM A537 Class 1 are often preferred to ensure sufficient impact toughness and fracture resistance.

The final tank plate material must always align with project-specific requirements for mechanical properties, weld performance, inspection standards, and long-term service reliability.

Steel Plate Grades Commonly Used in Oil & Gas Storage Tanks

The following grades are widely specified as tank plate or gas steel plate materials in oil & gas storage tanks, separators, and pressure-containing equipment.

1. ASTM A516 (Grades 55 / 60 / 65 / 70)

This is the most widely accepted material for pressure vessels and tank shells due to its excellent toughness and moderate strength. A516 Grade 70 is particularly common in crude oil tanks and separators.

Key Technical Features:

• Normalized carbon steel with excellent notch toughness
• Weldable using standard procedures (SMAW, GTAW, SAW)
• Compliant with ASME, API, and PED codes

Common Uses:

• Crude oil storage tanks
• Gas separators and flare drums
• Flash tanks and knock-out drums

2. ASTM A537 (Class 1 / Class 2)

A537 is a quenched and tempered pressure vessel steel, typically used in applications requiring higher impact resistance or thicker wall construction.

Key Technical Features:

• Superior strength and ductility
• Excellent resistance to brittle fracture
• Designed for high-pressure and high-temperature environments

Suitable for:

• Pressurized fuel tanks
• Spherical gas tanks
• Oil field separators and scrubbers

For applications requiring design temperatures below -20°C, Class 1 is preferred due to its better impact performance.

3. EN 10028 P265GH / P295GH / P355GH

For European projects, these EN-compliant plates are often used as equivalents to A516, offering similar properties with CE-marking capability and dual certification options.

Technical Advantages:

• Excellent pressure and heat resistance
• Low carbon content ensures good weldability
• Widely accepted in refinery and petrochemical EPC tenders

Additional Technical Considerations in Tank Plate Selection

Choosing the right grade is only one part of the decision. Experienced steel plate buyers—from tank manufacturers, refinery EPCs, to oil terminal constructors—often also evaluate:

1. Impact Toughness Requirements

• In colder climates or cryogenic applications (LNG or LPG tanks), steel plates must meet impact resistance standards such as Charpy V-notch @ -20°C or -46°C.
• A516 and A537 can be ordered with supplementary requirements like HIC resistance or NACE MR0175 compliance.

2. Weldability

• Lower carbon equivalents (Ceq) improve weldability and reduce the need for post-weld heat treatment (PWHT).
• All steel plates must be delivered in a condition suitable for multipass welding—especially for vertical tank seams.

3. Plate Thickness and Tolerance

• Typical wall thickness: 6mm–60mm
• Tank bottom plates may require thicker steel with lower sulfur for better flattening.
• Dimensional tolerance should meet ASTM A20 or EN 10029 Class A/B standards.

4. Testing and Certification

• Buyers often require:
  • Ultrasonic Testing (UT): EN10160 or ASTM A578 Level B/C
  • Visual Inspection: EN10163
  • Hydrostatic Test Requirements: Based on ASME/API guidelines
  • MTCs with EN10204 3.1 or 3.2 format

Surface Conditions and Additional Processing

For long-term performance, buyers may request:

• Shot blasting and priming (Sa2.5)
• Oil coating or zinc-based passivation layers
• Edge preparation (beveling, trimming)
• Custom-cut shapes or welded subassemblies

These can all be pre-processed at the mill or by the supplier, significantly reducing fabrication time on-site.

Packaging & International Delivery

Steel plates are typically packed with moisture protection and identification markings to ensure traceability during transportation. Documentation such as mill test certificates and inspection reports is commonly provided based on project requirements.

Summary: How to Choose the Right Steel Plate

When sourcing steel plate for the oil & gas industry, prioritize:

Factor	Recommendation
Pressure Rating	A516, A537, or P355GH
Impact Resistance	A516 Gr. 70N / A537 Class 1
Temperature Sensitivity	A516 with low-temp test or alloy-enhanced plate
Code Compliance	ASTM / ASME / API / EN standards
Weldability	Low Ceq, normalized delivery, UT-tested
Logistics	Plate dimensions suitable for container or bulk delivery

FAQs of Steel Plate for the Oil & Gas Industry

• Q1: What is the most common steel plate used in oil storage tanks?
  A516 Grade 70 is the most widely used plate due to its high strength, weldability, and cost efficiency.
• Q2: What’s the difference between A516 and A537 steel plates?
  A516 is normalized carbon steel for medium pressure, while A537 is quenched and tempered for higher pressure and improved impact performance.
• Q3: Can A516 and A537 steel plates be used for LNG or cryogenic tanks?
  Yes, when supplied with low-temperature impact testing and NACE compliance, A516 and A537 plates are suitable for cryogenic or low-temp service.

For engineering teams and EPC contractors moving from material selection to procurement, CJM provides certified steel plates for oil & gas storage tanks and pressure vessels, including ASTM A516 Grade 70, A537 Class 1, and EN 10028 P355GH, with ultrasonic testing and custom cutting services available based on project requirements.

WhatsApp: +86 181 9190 6640
Email: info@cjmstainlesssteel.com