ClassNK Approves Corrosion-Resistant Cable for Offshore Wind Use

Key Takeaways

• First ClassNK approval for corrosion‑resistant SPWC
• 7 mm galvanized steel wires, polyethylene coating
• High fatigue strength, suitable for floating turbine moorings
• Replaces steel chains, synthetic ropes in offshore wind
• Enables flexible, lower‑maintenance mooring configurations

Summary

ClassNK has granted both a Manufacturing Procedure Approval and a Type Approval for KOBELCO Wire Company's new semi‑parallel wire cable (SPWC), marking the society’s first endorsement of this corrosion‑resistant product. The cable features 7 mm galvanized steel wires coated in polyethylene, delivering high fatigue strength and superior resistance to marine corrosion. Designed for mooring floating offshore wind turbines, it offers a durable alternative to traditional steel chains and synthetic ropes. The certification follows ClassNK’s “Guidelines for Floating Offshore Wind Turbines,” underscoring the cable’s compliance with industry safety standards.

Pulse Analysis

Offshore wind is scaling rapidly, with floating turbines now accounting for a growing share of new capacity. These platforms rely on mooring systems that can withstand relentless wave action and salty environments, yet traditional steel chains corrode quickly and synthetic ropes can suffer from abrasion and UV degradation. KOBELCO’s semi‑parallel wire cable (SPWC) enters the market as a purpose‑built answer, combining metallic strength with a protective polyethylene sheath to tackle the harsh marine conditions that have long plagued offshore installations.

The SPWC’s construction uses 7 mm galvanized steel strands encased in a polyethylene coating, delivering a blend of high fatigue resistance and corrosion immunity. This design translates into longer service intervals, reduced inspection costs, and the ability to configure moorings more flexibly than rigid chains allow. Operators can expect lighter handling, easier installation, and a lower total cost of ownership, especially as turbine sizes increase and deeper water sites become economically viable. The cable’s durability also mitigates the risk of sudden failure, a critical safety factor for floating platforms.

ClassNK’s certification carries weight across the maritime and renewable sectors, signaling that the cable meets rigorous safety and performance benchmarks. By formally recognizing the product, the classification society paves the way for broader industry acceptance and may influence future offshore wind standards. As developers chase higher capacity factors and faster project timelines, such certified, corrosion‑resistant solutions could become a cornerstone of the next wave of offshore wind growth, driving both cost efficiencies and reliability improvements.