DNV Grade D Shipbuilding Steel Plate - DNV Certified Ordinary-Strength Marine Structural Steel Plate

1. What is DNV Grade D shipbuilding steel plate?

DNV Grade D shipbuilding steel plates are ordinary-strength, low-alloy, high-toughness structural steel plates for ship hulls certified by DNV (Det Norske Veritas); they are classified as fine-grained killed steel. It features excellent low-temperature impact resistance (≥ 27J at -20°C), stable mechanical properties (yield strength ≥ 235 MPa, tensile strength 400 - 520 MPa), excellent weldability, and resistance to marine corrosion. Widely used in shipbuilding and offshore auxiliary structure engineering in temperate and cold-water regions, it is a cost-effective structural steel plate for marine applications.

2. Meaning of the Designation

NV: Certified by the Det Norske Veritas (DNV)

D: Quality grade D (Impact testing must be conducted at -20°C)

Chemical Composition (Heat Analysis, wt %)

Carbon Equivalent (wt %)

Calculation formula (IIW): CEV = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15

Tensile test

Charpy (V-notch) impact test

DNV Grade D shipbuilding steel plates are widely used in medium- and low-load structures in shipbuilding, offshore engineering, and marine support facilities, specifically including:

1. Main Ship Structure (Primary Applications)

Deck System: Main deck, superstructure deck, hatch coamings (typical applications).

Hull Plating: Side plating, bottom plating, inner bottom plating.

Bulkheads and Framing: Transverse and longitudinal bulkheads, ribs, beams, stringers, girders, and bulkhead stiffeners.

Applicable Vessel Types: Bulk carriers, oil tankers, container ships, general cargo ships, offshore engineering vessels, tugs, fishing vessels, and other mainstream commercial ships.

Operating Temperature: Suitable for waters at -20°C and above.

2. Ship Outfitting and Auxiliary Structures

Superstructure exterior walls, walkways, platforms, and handrail bases.

Marine crane bases, anchor winches, capstan bases, chafing guides, and mooring post reinforcement plates.

Internal stiffeners for cargo holds and ballast tanks, bilge wells, and bulkhead structures.

3. Offshore Engineering and Structures

Upper modules, decks, and support structures of jack-up/semi-submersible platforms.

Subsea pipelines, risers, jetties, mooring piers, and wharf structural components.

Structures in non-extremely cold regions for coastal power plants, port machinery, and offshore wind turbine foundations.

4. Ship Repair and Refitting

Hull plating replacement, deck refurbishment, bulkhead modifications, and structural reinforcement.

Life extension of older vessels, damage repair, and superstructure heightening and modifications.

Key Product Features and Technical Advantages

1. Authoritative DNV Certification

Fully compliant with DNV shipbuilding codes, with complete certification documentation. Supports official DNV inspections and international project acceptance, making it suitable for global shipbuilding and offshore engineering tender projects.

2. Excellent Low-Temperature Toughness

Passes the -20°C low-temperature impact test, effectively reducing the risk of brittle fracture in structures operating in cold waters and harsh marine environments.

3. Excellent Workability

Features good weldability with no tendency to crack; easy to cut, bend, and form, significantly improving construction efficiency and reducing construction costs.

4. Reliable Structural Stability

Uniform steel composition with low impurity content ensures stable tensile and yield strengths. Possesses excellent resistance to seawater and marine atmospheric corrosion, effectively extending the service life of hulls, decks, and offshore auxiliary structures.

5. Wide Range of Custom Specifications

Supports customization of thickness, width, and length; offers Z-direction properties (Z15/Z25/Z35), ultrasonic testing, and special heat treatment services to meet the needs of specific projects.

Our Advantages and Service Guarantees

1. Reliable Factory Credentials

We hold DNV-certified qualifications for the production of shipbuilding steel plates, ensuring a stable supply at reasonable prices.

2. Ample Inventory and Prompt Delivery

We maintain ample stock of standard specifications and support both bulk wholesale orders and small-batch trial orders, effectively shortening the customer’s procurement cycle.

3. Full Quality Traceability

We provide complete Material Test Certificates (MTCs) and DNV certification, and support third-party inspections by SGS, BV, and others.

4. Professional Custom Processing

We offer cutting, bending, heat treatment, surface treatment, and further processing services to meet diverse engineering needs.

5. Extensive Global Export Experience

We are well-versed in international shipping and export customs clearance procedures, and maintain a stable supply to markets in Europe, Southeast Asia, the Middle East, and beyond.

• Differences Between DNV Grade A, B, D, and E Shipbuilding Steel Plates