GNEE Steel S960Q Ultra-High-Strength Steel Plates Batch Shipped To Japan

Recently, good news came from the high-end plate production base under GNEE Steel as a batch of S960Q ultra-high-strength structural steel plates weighing a total of 200 tons was officially shipped from Shanghai Port to Osaka Port in Japan after passing multiple rounds of rigorous inspections. These steel plates will be supplied to a top Japanese construction machinery manufacturer for the production of core load-bearing structures of ultra-large crawler cranes. This marks the first entry of GNEE Steel's S960Q steel plates into the Japanese high-end construction machinery market. With excellent quality complying with the Japanese JIS G 3128 standard, it has broken the long-term monopoly of European and American enterprises in this field, demonstrating the technical strength of China's ultra-high-strength steel plates.

According to the GNEE Steel Technical Director, the S960Q steel plates shipped to Japan were customized for the precision manufacturing needs of Japanese customers, with core technical parameters reaching the international advanced level:

• Yield Strength (≥): 960MPa
• Tensile Strength Range: 1050-1250MPa
• Elongation (≥): 10%
• Impact Energy (-40℃) (≥): 40J
• Steel Plate Thickness: 10-60mm
• Width: 2200-3000mm
• Length: Customized according to customer drawings (8000-12000mm)

As a leading enterprise in the global precision construction machinery field, the Japanese customer has set extremely high requirements for the stability of mechanical properties, dimensional accuracy, and surface finish of steel plates. Their core assessment indicators far exceed industry conventional standards-steel plate thickness tolerance must be controlled within ±0.2mm, surface roughness Ra≤3.2μm, and no visible micro-defects are allowed. Since these steel plates will be directly used in critical components such as crane booms and turntables, they directly determine the load safety and operational accuracy of the equipment.

During the production and processing of this order, the technical team faced three core technical challenges:

1. Control of Thick Plate Weldability

As an ultra-high-strength steel, S960Q has a high carbon equivalent, resulting in a strong hardening tendency during welding of thick plates, which is extremely prone to cold cracks. The Japanese customer requires the yield strength of the welded joint to be no less than 95% of the base material. To address this issue, the technical team conducted special research and development in collaboration with universities, adopting a "preheating + ultra-low hydrogen welding + post-heat stress relief" three-in-one process. The preheating temperature was precisely controlled at 180-220℃, imported low-hydrogen flux-cored wires were selected, the welding heat input was strictly controlled between 20-30kJ/cm, and immediate post-weld heat treatment at 250℃×2h was performed. Testing by a third-party inspection institution shows that the yield strength of the welded joint reached 980MPa, fully meeting the customer's requirements.

2. Control of Steel Plate Surface Accuracy

The control of steel plate surface accuracy is difficult, and conventional rolling processes cannot meet the requirement of Ra≤3.2μm. To address this, the production workshop used a high-precision four-high cold rolling mill imported from Germany and added three surface treatment processes: "cold rolling + precision grinding + polishing". Meanwhile, inert gas protection was adopted throughout the production process to avoid surface oxidation of the steel plates. The final delivered steel plates all met the surface finish requirements.

3. Control of Steel Plate Flatness

The flatness requirement of the steel plates is stringent, with the customer specifying that the flatness error per meter should be ≤1mm. The technical team optimized the rolling rhythm, adjusted the roll crown curve, and added a leveling process after finishing. Multiple leveling operations were performed using a 16-roll precision leveling machine, finally achieving a flatness error controlled within 0.8mm/m.

"Japan's market is globally recognized for its stringent requirements on industrial product quality. The successful passage of the full-range inspection by the customer for these S960Q steel plates is an affirmation of our technical, production, and quality control capabilities," said a GNEE Steel official. To align with Japan's market environmental philosophy, the steel plates adopted a dual anti-corrosion treatment of chromium-free passivation + water-based anti-rust paint, which not only improved the anti-corrosion performance by 30% but also fully complies with the Japanese RoHS 2.0 environmental standard.

This order was completed in just 35 days from technical docking, sample trial production to batch delivery, and the efficient response capability has also won high praise from customers. It is understood that GNEE Steel has obtained ISO 9001 quality management system certification, Japanese JIS certification, and EU CE certification. This batch supply will lay a solid foundation for the company to further expand the Japanese and Southeast Asian high-end construction machinery markets.

Request A Quote

In recent years, with the global development of construction machinery towards large-scale and precision, the demand for ultra-high-strength steel plates such as S960Q has continued to grow. With years of technical accumulation, GNEE Steel has formed a complete industrial chain for S960Q steel plates from R&D, production to processing, with products widely used in high-end fields such as construction machinery, wind power, and nuclear power. This entry into the Japanese market will further enhance the company's brand influence in the global ultra-high-strength steel plate market.

Products Specification

S960QChemical Composition

S960Q Mechanical Property

Products Applications

1. Construction: S960 steel is widely used in the construction industry for the fabrication of high-rise buildings, bridges, and infrastructure projects. Its high strength and toughness ensure the structural integrity and safety of these structures.

2. Heavy Machinery: S960 steel is employed in the manufacturing of heavy machinery and equipment, such as cranes, excavators, and mining machinery. Its superior strength allows for the construction of robust and reliable machinery capable of withstanding heavy loads.

3. Transportation: S960 steel is utilized in the transportation sector for the construction of truck chassis, trailers, and railway components. Its high strength-to-weight ratio enables the development of lightweight yet durable transportation systems.

4. Offshore and Marine Structures: S960 steel is suitable for offshore and marine applications, including oil rigs, shipbuilding, and offshore platforms. Its excellent toughness and resistance to corrosion make it an ideal choice for these demanding environments.