Inconel 718 Bar is a high-strength nickel-chromium alloy bar designed for marine and offshore components that require excellent mechanical strength, corrosion resistance, fatigue resistance, and long-term reliability under pressure, vibration, seawater atmosphere, and harsh operating conditions.
For offshore oil & gas, subsea equipment, marine engineering, valve manufacturing, fastener production, pump components, shafts, and precision machined parts, Emily PIPE supplies Inconel 718 bars in standard and customized sizes according to customer drawings, technical specifications, heat treatment requirements, and application environments.
| Item | Details |
|---|---|
| Executive Standards | 1. International Material Standards: ASTM B637, AMS 5662, DIN 17752, EN 2.4668, ISO 6208
2. Classification Society Standards: ABS (American Bureau of Shipping), DNV (Det Norske Veritas), LR (Lloyd’s Register), BV (Bureau Veritas), CCS (China Classification Society), RINA (Registro Italiano Navale) 3. Quality System Certification: ISO 9001, ISO 14001, OHSAS 18001 4. Testing Standards: ASTM E8 (Tensile), ASTM E23 (Impact), ASTM G48 (Seawater Corrosion), ASTM E466 (Fatigue), ASTM A388 (Ultrasonic Testing) |
| Material Grade | 1. Main Grade: Inconel 718 (Marine & Offshore Grade)
2. International Designations: UNS N07718, W.Nr. 2.4668, EN 2.4668 3. Equivalent Grades: GB GH4169, JIS NW7718, fully compatible with all global marine engineering standards |
| Chemical Composition (Weight %) | 1. Nickel (Ni): 50.00 – 55.00
2. Chromium (Cr): 17.00 – 21.00 3. Iron (Fe): 14.00 – 18.00 4. Molybdenum (Mo): 2.80 – 3.30 5. Niobium + Tantalum (Nb+Ta): 4.75 – 5.50 6. Titanium (Ti): 0.65 – 1.15 7. Aluminum (Al): 0.20 – 0.80 8. Carbon (C): ≤0.08 9. Manganese (Mn): ≤0.35 10. Silicon (Si): ≤0.35 11. Phosphorus (P): ≤0.015 12. Sulfur (S): ≤0.015 13. Copper (Cu): ≤0.30 |
| Mechanical Properties (Marine-Grade Annealed State) | 1. Tensile Strength: ≥1240 MPa
2. 0.2% Yield Strength: ≥860 MPa 3. Elongation (δ5): ≥15% 4. Reduction of Area (ψ): ≥30% 5. Hardness (HB): 300 – 380 6. Low-Temperature Impact Toughness (-60℃): ≥45 J (polar region requirement) 7. Fatigue Strength (10⁷ Cycles): ≥550 MPa 8. High-Temperature Tensile Strength (650℃): ≥900 MPa 9. Corrosion Rate: ≤0.015mm/year in 3.5% NaCl solution (25℃) 10. Stress Corrosion Cracking Resistance: No failure after 1000 hours in boiling 42% MgCl₂ solution |
| Dimensional Tolerance (Marine-Grade Precision) | 1. Diameter Tolerance: Precision Grade (≤50mm): ±0.015mm; Standard Grade (50-100mm): ±0.02mm; Heavy Section (100-200mm): ±0.03mm
2. Length Tolerance: Fixed Length (1m-6m): ±0.2mm/m; Maximum Full-Length Tolerance: ≤0.8mm; Custom Length up to 12m available 3. Straightness: ≤0.15mm/m, Full-Length Straightness Error: ≤0.4mm/6m 4. Roundness: ≤0.01mm (≤50mm); ≤0.015mm (50-100mm); ≤0.02mm (100-200mm) 5. Surface Finish: Ra ≤0.8μm, optional polished finish Ra ≤0.4μm for critical applications |
| Why the Marine & Offshore Industry Uses This Material (Detailed) | 1. Unrivaled Seawater Corrosion Resistance: Unlike carbon steel (corrodes in 2-3 years) and 316L stainless steel (prone to pitting/crevice corrosion in 5-7 years), Inconel 718 forms a self-healing chromium-molybdenum passive film that resists chloride ion attack for over 25 years. It is immune to microbiologically influenced corrosion (MIC) common in seawater systems.
2. Superior Stress Corrosion Cracking (SCC) Resistance: Marine components are subjected to combined tensile stress and corrosive media, the leading cause of catastrophic failure. Inconel 718 exhibits exceptional SCC resistance in chloride, hydrogen sulfide and sour gas environments, preventing sudden component fracture at sea. 3. Extreme Fatigue and Impact Resistance: Offshore equipment endures 24/7 vibration from engines, propellers and wave action, plus impact loads from storms, ice and collisions. Inconel 718’s high fatigue strength and toughness reduce failure rates by 70% compared to conventional alloys. 4. Wide Temperature Range Performance: Operates reliably from -60℃ (Arctic offshore) to 650℃ (engine exhaust systems), maintaining full mechanical properties without low-temperature brittleness or high-temperature softening. 5. Excellent Processability: Easily forged, machined and welded without cracking. Weld joints retain 90%+ of base metal strength and corrosion resistance, critical for on-site repairs in remote offshore locations. 6. Proven Long-Term Reliability: Has been used in North Sea, Gulf of Mexico and South China Sea offshore projects for over 40 years, with zero material-related failures in properly specified applications. 7. Lowest Total Lifecycle Cost: While initial material cost is higher, 3x longer service life and 80% reduction in maintenance costs deliver 50%+ total cost savings over the asset’s lifetime. |
| Application Scenarios & Corresponding Customers (Detailed) | Application Scenarios:
Marine Vessels: 1. Propulsion Systems: Propeller shafts, stern tubes, rudder stocks, gearbox gears and shafts, thruster components 2. Power Systems: Engine crankshafts, connecting rods, turbocharger blades, exhaust manifolds, fuel injection components 3. Seawater Systems: Seawater pump shafts, valve stems, heat exchanger tubesheets, desalination plant components 4. Deck Machinery: Crane booms, winch drums, anchor windlass shafts, hydraulic cylinder rods, mooring equipment 5. Special Vessels: LNG carrier cryogenic components, chemical tanker corrosion-resistant parts, naval ship structural components Offshore Engineering: 1. Oil & Gas Platforms: Riser connectors, subsea wellhead components, BOP (Blowout Preventer) parts, pipeline flanges 2. Subsea Equipment: Subsea pump shafts, valve bodies, manifold components, umbilical terminations 3. Offshore Wind: Wind turbine main shafts, gearbox components, foundation bolts, underwater connectors 4. Deepwater Systems: ROV (Remotely Operated Vehicle) structural parts, subsea sensor housings, mooring chains Corresponding Customers: 1. Global commercial shipyards (container ships, bulk carriers, LNG carriers, cruise ships) 2. Naval shipyards and defense contractors (warships, submarines, coast guard vessels) 3. Offshore EPC contractors (oil & gas platforms, offshore wind farms, subsea pipelines) 4. Marine equipment manufacturers (engines, propellers, pumps, valves, deck machinery) 5. Oil & gas supermajors (ExxonMobil, Shell, BP, TotalEnergies) and national oil companies 6. Offshore wind farm developers and operators 7. Ship owners, shipping lines and vessel management companies 8. Marine repair yards and offshore maintenance service providers |
| Corresponding User Needs in Marine & Offshore Industry (Detailed) | 1. Extreme Longevity Demand: Offshore assets have design lives of 25-40 years (platforms up to 50 years). Users require materials that maintain performance without replacement for the entire asset lifecycle.
2. Zero-Failure Reliability: Equipment failure at sea costs $100,000+ per day in downtime, plus potential environmental disasters. Users demand materials with proven track records of zero catastrophic failures. 3. Multi-Environment Adaptability: Assets operate in diverse conditions from Arctic ice fields to tropical oceans, requiring materials that perform across extreme temperature, pressure and salinity ranges. 4. Stringent Certification Requirements: All materials must be certified by major classification societies. Users need suppliers who can provide complete documentation and third-party verification. 5. Full Traceability: Regulatory bodies require complete material traceability from melt to finished product. Users need suppliers with robust traceability systems that meet IMO and offshore industry standards. 6. On-Site Repairability: Remote offshore locations make replacement difficult. Users need materials that can be welded and repaired on-site without specialized equipment. 7. Cost-Effectiveness: While initial cost is a consideration, users prioritize total lifecycle cost, including maintenance, downtime and replacement expenses. 8. Customization Capability: Offshore projects often require unique sizes, shapes and performance characteristics. Users need suppliers who can provide custom solutions with short lead times. 9. Sustainability Compliance: Increasingly, users require materials that are recyclable and meet environmental regulations for offshore operations. |
| Common Related Products in Marine & Offshore Industry | 1. Inconel 718 Marine Forgings: Large components such as propeller shafts, crankshafts, riser flanges and platform structural parts
2. Inconel 718 Marine Welding Wire: ERNiCrFe-3 and ERNiCrMo-3 welding consumables for marine-grade Inconel 718 3. Inconel 718 Seamless Tube: For seawater pipelines, heat exchanger tubes, hydraulic lines and subsea umbilicals 4. Inconel 718 Sheet/Plate: For hull reinforcements, equipment casings, heat exchanger plates and blast walls 5. Inconel 718 Fasteners: High-strength bolts, nuts, studs and screws for critical offshore assemblies 6. Inconel 718 Precision Machined Parts: Finished components such as valve stems, pump impellers, gear shafts and sensor housings |
| Why Choose Us (Emily PIPE) | 1. 20+ Years of Marine & Offshore Expertise: We have supplied alloy materials to over 500 marine and offshore projects worldwide, with deep understanding of industry requirements and challenges.
2. Complete Classification Society Certifications: Our products hold ABS, DNV, LR, BV and CCS certifications, ensuring compliance with all international marine regulations. 3. Marine-Specific Quality Control: We implement a dedicated quality control process for marine products, including 100% non-destructive testing and corrosion resistance verification. 4. Full Material Traceability: Every bar comes with a unique heat number and complete traceability documentation from raw material to finished product, meeting IMO and offshore industry requirements. 5. Advanced Customization Capability: We can produce custom sizes, lengths and surface finishes according to your drawings and technical specifications, with lead times as short as 15 days. 6. Professional Technical Support: Our team of metallurgical engineers provides expert material selection guidance, welding parameters and machining recommendations for marine applications. 7. Global One-Stop Service: We handle everything from material selection and production to international shipping and customs clearance, with reliable logistics partners ensuring on-time delivery to any port worldwide. |
| Inquiry Guidance Words | 1. If you need marine & offshore grade Inconel 718 bar for your project, please send us your specific requirements including dimensions, quantity, required certifications and delivery date, and we will provide a detailed quotation within 12 hours.
2. For any questions about material properties, classification society certification, testing reports or processing technology, our marine industry specialists are available to assist you promptly. 3. Emily PIPE is your trusted partner for high-performance marine alloy materials. Contact us today to discuss how we can support your next marine or offshore project with reliable, cost-effective solutions. |
| Supplementary Information | 1. Comprehensive Test Reports: Each batch comes with a full Material Test Report (MTR), including chemical composition, mechanical properties, non-destructive testing results and corrosion resistance data.
2. 100% Non-Destructive Testing: All products undergo ultrasonic testing (UT), eddy current testing (ET) and surface inspection to ensure no internal or surface defects. 3. Marine-Grade Packaging: We use anti-corrosion wrapping, wooden crates and steel strapping to protect products during long-distance sea transportation, with clear identification and traceability labels. 4. Urgent Order Support: We maintain a large inventory of standard marine-grade Inconel 718 bar sizes, enabling us to fulfill urgent orders within 7 days. 5. Small Batch Production: We support small batch orders for prototype development, equipment repairs and spare parts, with no minimum order quantity for standard sizes. 6. After-Sales Service: We provide lifetime technical support for all our products, including on-site assistance for material-related issues and replacement parts for warranty claims. |