High-Strength Bolt Connection Set for Wind Turbine Tower — Hex Nut

This product is specifically designed for the high-strength connection requirements of wind turbine generator towers, serving as a key fastener in the connection set. The product is strictly manufactured in accordance with the energy industry standard NB/T 31082-2016, with a property class of Grade 10. Common specifications cover M36 to M64. The commonly used material is high-quality medium-carbon alloy steel 35CrMoA or 42CrMoA, subjected to strict quenching and tempering heat treatment, ensuring excellent mechanical properties and long-term reliability in the demanding service environment of wind farms.

I. Product Features

High Standard Compliance: Strictly produced in accordance with NB/T 31082-2016 standard, with stringent dimensional accuracy and form/position tolerance control, ensuring a high degree of interchangeability and consistency.

High-Performance Alloy Steel Material: Selected 35CrMoA/42CrMoA premium alloy structural steel, with precise chemical composition control, ensures the material possesses excellent hardenability and cleanliness (low content of harmful impurities such as S and P).

Strict Quenching and Tempering Treatment: Through quenching and high-temperature tempering treatment, ensures uniform hardness across the entire cross-section of the nut, achieving the optimal balance between strength and toughness, effectively avoiding decarburization and surface cracks.

Reliable Corrosion Protection: Typically adopting surface treatment processes such as Dacromet, zinc-chromium coating, or sherardizing, possessing excellent salt spray corrosion resistance, effectively resisting harsh atmospheric environments such as marine and high-humidity conditions.

Complete Product Traceability: The product body is marked with clear property class and material identification; each piece carries a unique heat/batch number, enabling full-process quality traceability from raw steel to finished product.

II. Product Advantages

Long Fatigue Life: Specifically designed for the fatigue working conditions of wind turbine tower vibration and sway; through alloying and quenching & tempering treatment, fatigue resistance far exceeds that of ordinary carbon steel nuts, significantly reducing the risk of fretting wear and fatigue fracture.

Excellent Anti-Seizing Performance: Precise matching of material and hardness, combined with special surface coatings, effectively reduces thread seizing under high preload conditions, facilitating construction installation and post-maintenance disassembly.

Outstanding Comprehensive Mechanical Properties: While ensuring high strength, it possesses good plasticity and low-temperature impact toughness, capable of adapting to a wide temperature range from extreme heat to severe cold, maintaining reliable mechanical properties even at -40°C.

Stable and Reliable Quality: From raw material incoming inspection to finished product delivery, passing full-item inspections including chemical composition, mechanical properties, metallographic structure, and surface quality, ensuring highly stable product quality and providing permanent safety assurance for towers.

III. Application Areas

Core Application: Flange pairs connecting the sections of wind turbine generator tower barrels, between barrel and transition section, and between tower and nacelle.

Anchor System: Anchor connections between tower foundation and foundation ring/anchor bolt cage platform.

Critical Component Connection: High-strength fastening connections of large steel structural components within wind turbine generators that are subjected to alternating loads and have extremely high fatigue strength requirements.

Similar Scenarios: Also applicable to other large heavy-duty steel structural engineering projects with high-strength and high-reliability requirements, such as large steel structural bridges and offshore engineering platforms.