RINA E32 Shipbuilding Steel Coil
RINA E32 Shipbuilding Steel Coil: High-Strength Hull Structural Steel with Excellent Low-Temperature Toughness
RINA E32 is a high-strength hull structural steel certified by the Italian Classification Society RINA, widely used in shipbuilding and offshore structures with guaranteed minimum yield strength of 315 MPa and excellent impact toughness at -40°C.
Controlled rolling, normalizing rolling, or thermomechanical controlled process (TMCP); also suitable for hot forming, cutting, welding, and cold forming with precautions.
- Phone : +8618037372205
- Email : [email protected]
- WhatsApp: Contact via Whtsapp
- WeChat: +8618037372205
RINA E32 Shipbuilding Steel Coil Introduction
RINA E32 is a normalized or controlled rolled high-strength steel grade for shipbuilding, conforming to the RINA Rules for the Classification of Ships. It is typically supplied as coil or plate, with a minimum yield strength of 315 MPa and tensile strength ranging from 440 to 590 MPa. The steel offers good weldability, excellent notch toughness at low temperatures (designated 'E' class for -40°C), and resistance to brittle fracture, making it suitable for critical structural members in ships and offshore units operating in cold environments. It is produced with fine grain practice and may involve microalloying elements such as niobium, vanadium, or titanium to achieve required mechanical properties.
RINA E32 Shipbuilding Steel Coil Chemical Composition
The chemical composition of E32 conforms to RINA Rules. Carbon equivalent (CEQ) is controlled to ensure weldability. Refinement elements such as Nb, V, Ti may be added singly or in combination. For thicknesses above specified limits, additional requirements for alloy content or impact testing may apply.
| Element | Specified Value (max unless range given) | Remarks |
|---|---|---|
| C | ≤0.18 | Carbon |
| Mn | 0.90–1.60 | Manganese |
| Si | ≤0.50 | Silicon |
| P | ≤0.035 | Phosphorus |
| S | ≤0.035 | Sulfur |
| Al (acid soluble) | ≥0.015 | Total aluminum or acid soluble aluminum, for grain refinement |
| Nb | ≤0.05 | Niobium (Columbium), optional microalloy |
| V | ≤0.10 | Vanadium, optional microalloy |
| Ti | ≤0.02 | Titanium, optional microalloy; if used, total Al may be partly replaced |
| Cu | ≤0.35 | Copper, residual limit |
| Cr | ≤0.20 | Chromium, residual limit |
| Ni | ≤0.40 | Nickel, residual limit |
| Mo | ≤0.08 | Molybdenum, residual limit |
| N | ≤0.012 | Nitrogen, if bound by suitable elements, may be higher |
| CEQ (max) | ≤0.38 | Carbon equivalent = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15, typically ≤0.38 for thickness ≤50 mm |
RINA E32 Shipbuilding Steel Coil Thermal and Electrical Physical Properties
The following values are representative for normalized structural steel similar to E32. Actual properties may vary slightly depending on specific composition and processing. These values are not subject to mandatory testing per RINA rules but are useful for design calculations.
| Property | Typical Value | Unit | Condition / Remarks |
|---|---|---|---|
| Density (ρ) | 7.85 | g/cm³ | At room temperature (20°C) |
| Modulus of Elasticity (E) | 210 | GPa | At room temperature |
| Shear Modulus (G) | 81 | GPa | Approximate, based on E and Poisson's ratio |
| Poisson's Ratio (ν) | 0.29 | Elastic region, room temperature | |
| Thermal Expansion Coefficient (α) | 12 × 10⁻⁶ | K⁻¹ | Mean coefficient between 20°C and 100°C |
| Thermal Expansion Coefficient (α) | 13 × 10⁻⁶ | K⁻¹ | Mean coefficient between 20°C and 200°C |
| Thermal Expansion Coefficient (α) | 14 × 10⁻⁶ | K⁻¹ | Mean coefficient between 20°C and 400°C |
| Thermal Conductivity (λ) | 52 | W/(m·K) | At 20°C |
| Thermal Conductivity (λ) | 49 | W/(m·K) | At 100°C |
| Thermal Conductivity (λ) | 44 | W/(m·K) | At 200°C |
| Specific Heat Capacity (cp) | 460 | J/(kg·K) | At 20°C |
| Specific Heat Capacity (cp) | 500 | J/(kg·K) | At 100°C |
| Specific Heat Capacity (cp) | 540 | J/(kg·K) | At 200°C |
| Electrical Resistivity (ρ_e) | 0.18 × 10⁻⁶ | Ω·m | At room temperature, typical for carbon-manganese steel |
RINA E32 Shipbuilding Steel Coil Mechanical Properties
Tensile testing is performed in accordance with RINA requirements. Impact test (Charpy V-notch) values are minimum average energy for longitudinal specimens at -40°C; individual minimum is typically 70% of the average. Properties are valid for thicknesses as specified in the rules; for thicker products, requirements may be adjusted.
| Property | Specified Value | Unit | Test Condition / Remarks |
|---|---|---|---|
| Yield Strength (ReH) | ≥315 | MPa | Transverse or longitudinal, depending on product form and thickness; for thickness ≤50 mm, typical minimum 315 MPa |
| Tensile Strength (Rm) | 440–590 | MPa | For all thicknesses |
| Elongation (A) | ≥22 | % | Gauge length 5.65√S0 (typically 200 mm for plates); transverse specimen |
| Elongation (A) | ≥22 | % | For thickness ≤50 mm; may be adjusted for thinner sections |
| Bend Test (mandrel diameter) | D = 3a (where a = thickness) | 180° bend test, no cracks; for thickness ≤30 mm, mandrel diameter may be relaxed for higher strengths | |
| Charpy V-notch Impact Energy (KV) at -40°C | ≥31 J (average) | J | Longitudinal specimens; minimum single value 21 J |
| Charpy V-notch Impact Energy (KV) at -40°C | ≥24 J (average) | J | Transverse specimens, if applicable; minimum single value 17 J |
RINA E32 Shipbuilding Steel Coil Equivalent Material Standards and Substitute Grades
| Country/Region | Issuing Body / Standard | Grade | Remarks |
|---|---|---|---|
| International | IACS (International Association of Classification Societies) | EH32 | Common notation for high strength hull steel, E class (-40°C) with minimum yield 315 MPa; specific classification society prefixes apply |
| USA / International | ABS (American Bureau of Shipping) | EH32 | Pre 2019 designation; now ABS GR EH32 |
| Norway/Germany | DNV (Det Norske Veritas) | E32 | Former DNV grade, now DNV GL; same minimum yield and toughness |
| United Kingdom | Lloyd's Register (LR) | EH32 | Identical requirements |
| France | Bureau Veritas (BV) | EH32 | Matches IACS UR W11 |
| China | China Classification Society (CCS) | E32 | Conforms to CCS Rules |
| Japan | ClassNK (Nippon Kaiji Kyokai) | EH32 | Same as IACS |
| Korea | Korean Register (KR) | EH32 | Equivalent |
| Russia | Russian Maritime Register of Shipping (RS) | E32 | May be designated as E32 or E32S depending on delivery condition |
RINA E32 Shipbuilding Steel Coil Application Introduction
RINA E32 steel coil is primarily used in shipbuilding and offshore engineering where high strength, good weldability, and low-temperature toughness are essential. Typical applications include structural components that are loaded dynamically and exposed to cold service conditions.
Product Applications: Hull plates (shell, deck, bottom, side), Structural members (stiffeners, girders, beams, bulkheads), Pressure hulls for submersibles (with additional certification), Offshore structural tubulars, Caissons, sea chests, and sea water piping systems
Processed into products: Ship frames, longitudinal stiffeners, and transverse webs, Web frames and stringers, Hatch coamings and covers, Rudder horns and stock brackets, Brackets and connections in highly stressed areas, Helideck support structures, Transition pieces for monopile foundations, Lifting lugs and padeyes
Application industries: Shipbuilding (merchant vessels, naval ships, passenger ships, ferries), Offshore oil and gas (platforms, jackets, decks, modules), Marine equipment (crane pedestals, winch foundations), Port and harbor infrastructure (fender panels, lock gates), Renewable energy (offshore wind turbine foundations, transition pieces)
RINA E32 Shipbuilding Steel Coil Similar Alternative Materials
| Country/Region | Standard / Specification | Grade | Remarks |
|---|---|---|---|
| European Union | EN 10025-3 | S355N/NL | Normalized fine grain structural steel; S355N has minimum yield 355 MPa, impact at -20°C (NL at -50°C). Not ship-class specific but similar mechanical properties; needs additional certification if used for marine |
| European Union | EN 10025-4 | S355M/ML | Thermomechanical rolled; similar strength, with ML having impact at -50°C. Can be an alternative for non-marine welded structures |
| USA | ASTM A131 / A131M | EH32 | Standard specification for structural steel for ships; Grade EH32 under ASTM is equivalent to RINA E32, but ASTM EH32 is also a recognized shipbuilding steel |
| China | GB/T 712 | AH32, DH32, EH32 | Chinese shipbuilding standard; EH32 matches RINA E32 in strength and toughness class, but additional certification by RINA may be required |
Notes:
RINA E32 may be supplied with additional options: ultrasonic testing (e.g., in accordance with EN 10160 Class S1/E1 or ASTM A578), through-thickness properties (Z35 or Z25 per EN 10164), or seismic certification. Charpy test temperature may be reduced to -60°C for special applications. The steel can be delivered as coil, cut-to-length sheet, or plate. Maximum thickness limits for guaranteed properties depend on the mill's approval and the specific RINA rules; typical maximum for E32 is 100 mm, with possible reduction in minimum yield strength for thickness >50 mm as per RINA rules (e.g., 315 MPa up to 50 mm, 295 MPa for 50–70 mm, 275 MPa for 70–100 mm). Always refer to the latest RINA rules for exact requirements.
- Share
