Shipbuilding Forgings — The Most Diverse Marine Alloy Portfolio in Industrial Manufacturing
The global shipbuilding industry builds approximately 1,800–2,400 ships per year (all types — crude tankers, product tankers, bulk carriers, container ships, LNG carriers, cruise ships, RoPax ferries, naval vessels) with a total new construction value of $160–200 billion/year. The top three shipbuilding nations — South Korea (Hyundai Heavy Industries, Samsung Heavy Industries, Hanwha Ocean/DSME, Hyundai MIPO), China (CSSC/Hudong-Zhonghua, CSIC/Bohai Shipbuilding, Yangzijiang Shipbuilding), and Japan (Imabari Shipbuilding, Japan Marine United, Oshima Shipbuilding) — account for 95% of global commercial tonnage by GT. A modern Very Large Crude Carrier (VLCC — 320,000 DWT, $120–150 million newbuilding price) contains approximately 2,000 tonnes of forged steel components across its propulsion system (propeller shaft, intermediate shaft, thrust collar), steering system (rudder stock, rudder trunk, steering gear), mooring system (bollards, fairleads, capstan drums), and cargo handling system (hydraulic valve bodies, pump shaft forgings). The main engine crankshaft alone (MAN B&W 7G80ME-C10.5 — 7 cylinder, 2-stroke, 37 MW) is a single forged steel component of exceptional complexity: 42CrMo4 Q+T, 70–90 tonnes weight (the heaviest single steel forging in regular commercial manufacture after nuclear pressure vessel heads), with 14 forged crankpins and 8 forged main journals each at 380mm diameter, ground to Ra 0.4 µm surface finish for the hydrodynamic bearings. The classification society survey requirements — DNV GL, Lloyd's Register, Bureau Veritas, ABS, ClassNK mandatory witnessed testing at all stages — ensure that only the most technically capable forge shops supply marine propulsion forgings.
Hyundai Heavy Industries (HHI — Ulsan, South Korea — 45% of Korea's total shipbuilding capacity, world's #1 shipbuilder by volume) produced 96 vessels in 2023 including 18 LNG carriers (each with 4–5 propeller shaft forgings in Aquamet 22, 600–700mm OD × 10–14m long, weight 15–20 tonnes each — 90–100 tonnes of Aquamet 22 propeller shaft forgings per LNG carrier), 24 VLCCs, 18 container ships (24,000 TEU class), and 12 bulk carriers. Samsung Heavy Industries (Geoje Island, South Korea — world's #2 shipbuilder, specializing in LNG carriers and drillships): Samsung's Geoje shipyard built the first Samsung LNG carrier with 170,000 m³ GTT membrane containment (the Qatari QLNG fleet), and continues to be the world's leading LNG carrier builder alongside HHI. Hanwha Ocean (ex-Daewoo Shipbuilding and Marine Engineering DSME — acquired by Hanwha Group in 2023, Okpo Shipyard, Geoje): specializes in large submarines (Korean Navy Type 212A), LNG FPSOs (Prelude FLNG for Shell — world's largest floating structure), and VLOC (Very Large Ore Carriers). All three major Korean shipbuilders procure intermediate shaft forgings (42CrMo4 Q+T, DNV GL Grade II), rudder stock forgings (A694 F65), and mooring bollard forgings from DNV GL-approved forge shops. Shivam Forge's DNV GL Approval of Manufacturer (AoM) qualifies our Rajkot facility to supply marine forged components to HHI, Samsung, and Hanwha Ocean with CIF Busan/Ulsan transit of 12–16 days from Mundra.
Marine propeller shaft metallurgy presents one of the most complex alloy selection challenges in industrial procurement: the shaft must simultaneously resist seawater corrosion (3.5% NaCl brine at 20–35°C, permanently immersed), galvanic corrosion (the propeller is bronze alloy — 78% Cu, 16% Al, 4.5% Fe — which is anodic to carbon steel; if the shaft is carbon or alloy steel, it would rapidly corrode due to galvanic couple with the bronze propeller), cavitation erosion (propeller creates zones of intense low pressure causing bubble collapse on shaft surface), marine biofouling (barnacles, mussels, and biofilm forming on immersed surfaces), and bending fatigue (propeller weight + hydrodynamic forces create cyclical bending on shaft at 80–120 RPM for 25-year ship life = 1 billion fatigue cycles). The solution: Aquamet 22 (CuNiMnFe alloy — galvanically compatible with bronze propellers, immune to seawater corrosion, resistant to biofouling and cavitation). The alternative for smaller vessels is NiAlBronze (CuAl10Fe5Ni5 — 80% Cu, 10% Al, 5% Fe, 5% Ni) which provides even higher strength (Rm ≥740 MPa vs. Rm ≥620 MPa for Aquamet 22) and equivalent seawater corrosion resistance. Shivam Forge produces both Aquamet 22 and NiAlBronze (to DIN 17665 / ISO 1338) propeller shaft forgings, with 100% UT per EN 10228-1 and DNV GL survey — supplying propeller shaft ODs from 150mm (small ferries) to 700mm (VLCC and large container ships) in lengths up to 15m and weights up to 25 tonnes.
Shivam Forge's marine and shipbuilding forging market position: (1) Classification society approvals — DNV GL, Lloyd's Register, Bureau Veritas, and ABS survey capability; DNV GL Approval of Manufacturer for shaft and rudder stock forgings; IACS UR W7 compliance; (2) Complete marine alloy range — Aquamet 22/NiAlBronze propeller shafts, 42CrMo4 Q+T/34CrNiMo6 Q+T intermediate shafts and crankshaft blanks, A694 F65 rudder stocks, duplex 2205 thruster shafts; (3) Korean shipbuilding access — CIF Busan/Ulsan in 12–16 days from Mundra, serving HHI, Samsung Heavy Industries, and Hanwha Ocean; (4) European shipbuilding access — CIF Trieste/Monfalcone (Fincantieri) in 15–18 days, RINA and Lloyd's Register survey; (5) Indian Navy and Indian Shipbuilding — Mazagon Dock Shipbuilders (Mumbai — Indian Navy frigates, destroyers, submarines), Cochin Shipyard (IACC Indigenous Aircraft Carrier 1 — INS Vikrant), and Garden Reach Shipbuilders (Kolkata — naval corvettes, landing craft): domestic supply ex-Rajkot for Indian Navy shipbuilding program under Make in India. Contact our marine engineering team at +91-9265772827 for DNV GL certificate copies and Aquamet 22/NiAlBronze material data sheets.
