CCS Grade A Shipbuilding Steel Coil
CCS Grade A Shipbuilding Steel Coil: Composition, Properties and Equivalents
Detailed technical data for CCS Grade A shipbuilding steel coil, including chemical composition, mechanical properties, thermal and electrical physical properties, international equivalent grades, and application guide.
Hot rolling, cold forming, cutting, welding, bending, machining
- Phone : +8618037372205
- Email : [email protected]
- WhatsApp: Contact via Whtsapp
- WeChat: +8618037372205
CCS Grade A Shipbuilding Steel Coil Introduction
CCS Grade A is a general-strength hull structural steel certified by the China Classification Society (CCS) for shipbuilding applications. It is a low-carbon steel with excellent weldability and moderate strength, commonly supplied as plate, coil, and sections. Key characteristics:
- Minimum yield strength of 235 MPa
- Good toughness at ambient temperatures
- Excellent formability and weldability
- Stringent control of harmful elements ensures reliable performance in marine environments
CCS Grade A Shipbuilding Steel Coil Chemical Composition
Ladle analysis according to CCS Rules for Materials and Welding for Grade A hull structural steel. Control of carbon equivalent (Ceq) may be required depending on thickness. Values are maximum unless a range is indicated.
| Element | Standard Value (max, %) | Remarks |
|---|---|---|
| C (Carbon) | ≤ 0.21 | |
| Si (Silicon) | ≤ 0.50 | |
| Mn (Manganese) | ≥ 2.5 × C (typically 0.80 - 1.20) | Minimum 2.5 times carbon content |
| P (Phosphorus) | ≤ 0.035 | |
| S (Sulfur) | ≤ 0.035 | |
| Als (Acid-soluble Aluminum) | ≥ 0.015 (if fully killed) | Required for fully killed steel; optional for other deoxidation practices |
| Nb (Niobium) | 0.02 - 0.05 (optional) | Micro-alloying element may be added at manufacturer's option |
| V (Vanadium) | 0.05 - 0.10 (optional) | Micro-alloying element may be added |
| Ti (Titanium) | ≤ 0.02 (optional) | Can be used for grain refinement |
| Cu (Copper) | ≤ 0.35 (if specified) | |
| Cr (Chromium) | ≤ 0.20 (if specified) | |
| Ni (Nickel) | ≤ 0.40 (if specified) | |
| Mo (Molybdenum) | ≤ 0.08 (if specified) | |
| Ceq (Carbon Equivalent) | ≤ 0.40 (typical) | Ceq = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15; mandatory for thicker plates >50 mm |
CCS Grade A Shipbuilding Steel Coil Thermal and Electrical Physical Properties
Representative physical properties for low-carbon structural steel similar to CCS Grade A. Actual values may vary slightly with composition and processing. Thermal expansion and conductivity are essential for welding and structural design.
| Property | Typical Value | Unit | Test Condition / Remarks |
|---|---|---|---|
| Density (ρ) | 7.85 | g/cm³ | At 20°C |
| Elastic Modulus (E) | 200 - 210 | GPa | At 20°C |
| Shear Modulus (G) | 80 | GPa | Estimated from E and Poisson's ratio |
| Poisson's Ratio (ν) | 0.3 | - | At room temperature |
| Thermal Expansion Coefficient (α) | 11.5 - 12.5 | 10⁻⁶/K | 20°C to 100°C |
| Thermal Conductivity (λ) | 45 - 50 | W/(m·K) | At 20°C |
| Specific Heat Capacity | 460 - 500 | J/(kg·K) | At 20 - 100°C |
| Electrical Resistivity (ρ_e) | 0.15 - 0.22 | μΩ·m | At 20°C |
CCS Grade A Shipbuilding Steel Coil Mechanical Properties
Mechanical test results for CCS Grade A steel in as-rolled or normalized condition, based on CCS Rules. Transverse test specimens are used for plate/coil; longitudinal for sections. Impact testing is required at +20°C for Grade A (unless otherwise specified).
| Property | Standard Requirement | Unit | Test Condition |
|---|---|---|---|
| Yield Strength (ReH) | ≥ 235 | MPa | Room temperature, thickness ≤ 100 mm |
| Tensile Strength (Rm) | 400 - 520 | MPa | Room temperature, all thicknesses |
| Elongation (A) | ≥ 22 | % | Gauge length 5.65√S₀ (L₀ = 5.65√S₀); transverse specimen |
| Elongation (A) | ≥ 24 | % | Gauge length 5.65√S₀; longitudinal specimen |
| Impact Energy (KV2) | ≥ 27 (average); ≥ 20 (single value) | J | At +20°C, Charpy V-notch, transverse specimen |
| Bend Test (180°) | d = 2a (thickness ≤ 25 mm); d = 3a (thickness 25-50 mm) | - | No cracks or defects; a = specimen thickness |
CCS Grade A Shipbuilding Steel Coil Fully Equivalent Material Standards and Recommended Substitute Grades
| Country/Region | Standard | Grade | Remarks |
|---|---|---|---|
| International (IACS) | IACS UR W11 | General Hull Structural Steel - Ordinary Strength A | Reference standard for all classification societies |
| China | CCS Rules | A | Original certified grade |
| China | GB/T 712 | AH32, A | AH32 is higher strength; A is general strength equivalent |
| USA | ABS Rules | Grade A | Identical properties |
| UK | LR Rules | Grade A | Identical properties |
| Norway/Germany | DNV Rules | DNV A (NV A) | Identical properties |
| France | BV Rules | Grade A | Identical properties |
| Italy | RINA Rules | Grade A | Identical properties |
| Japan | NK (ClassNK) Rules | K A | Identical properties |
| Korea | KR Rules | Grade A | Identical properties |
| Russia | RMRS Rules | Grade A (PC A) | Equivalent per RMRS |
CCS Grade A Shipbuilding Steel Coil Application Introduction
CCS Grade A steel coil is predominantly used in the shipbuilding industry for hull construction and secondary structural components where high toughness is not critical at low temperatures. Due to its excellent weldability and forming characteristics, it is often processed into stiffeners and small parts. Typical processing includes:
- Hot rolling to final thickness
- Cut-to-length shearing
- Cold bending and forming
- Gas cutting and plasma cutting
- Submerged arc welding (SAW), gas metal arc welding (GMAW) and manual welding
Product Applications: Hull plates and shell plating (side, bottom, deck), Longitudinals and stiffeners (angles, bulb flats), Bulkheads and internal partitions, Superstructure panels, Casings and minor structural elements
Processed into products: Transverse frames and web frames, Stiffeners for decks and side shells, Brackets and collars, Non-critical foundations for machinery and equipment, Manhole covers and small hatches, Fabricated pipe supports and walkways
Application industries: Shipbuilding and offshore engineering, Marine equipment manufacturing, Barge and tug construction, Port and harbor structures, Structural engineering (with project-specific approval)
CCS Grade A Shipbuilding Steel Coil Near/Similar Substitute Materials
| Country/Region | Standard | Grade | Remarks |
|---|---|---|---|
| China | GB/T 1591 | Q235B / Q235C | Comparable low-carbon structural steel, but not certified for shipbuilding; lacks impact testing at +20°C for B; C has 0°C impact |
| European Union | EN 10025-2 | S235JR (1.0038) | Similar strength and chemistry; impact at +20°C (JR); not marine certified |
| USA | ASTM A36 | A36 | Widely used general structural steel, comparable strength but unspecified for ship structures |
| China | GB/T 712 | AH36 | Higher strength shipbuilding steel (min 355 MPa yield); may be used for weight reduction with design adjustments |
Notes:
Certification: Material must be produced by CCS-approved mills and stamped with the CCS mark and grade. Test certificates (3.1 or 3.2 per EN 10204) are mandatory.
Coil tolerances: Typically supplied according to GB/T 709 or EN 10029, with thickness tolerance classes as agreed.
Surface condition: As-rolled with normal mill scale; may be shot-blasted and shop-primed upon request.
Welding consumables: Compatible with common E7018, E71T-1, and ER70S-6 fillers; preheat not normally required below 50 mm thickness.
- Share
