Core equipment of steel metallurgical production lines including hot rolling mills, cold rolling mills, continuous casters, roller tables, straighteners, steel shearing equipment and heating furnace auxiliary machinery operate under extreme harsh working conditions of instantaneous ultra-large impact load, high-temperature thermal radiation from steel billets, circulating cooling water spray erosion, pervasive iron oxide dust, alternating cold and hot cycles and uninterrupted all-weather continuous rolling. Metallurgical steel industry is a continuous heavy-duty process industry. Bearing failure and shutdown will stall the whole production line. Retained high-temperature steel billets are prone to scrap. The restart process is complicated and causes huge output losses. Therefore, extremely high standards are required for bearing load limit, heat resistance, waterproof and anti-oxidation performance. Ordinary cylindrical roller bearings can hardly adapt to the harsh environment in metallurgical workshops, and frequent failures restrict production capacity. Steel rolling generates huge instantaneous impact and alternating composite loads. Ordinary bearings have insufficient matrix strength and are prone to raceway spalling, roller fragmentation and plastic deformation under long-term cyclic stress, leading to sudden shutdown. Steel billets continuously release high-temperature heat which conducts to bearing positions. Conventional bearings have insufficient upper temperature resistance limit. Long-term high temperature causes rapid carbonization and failure of grease, resulting in bearing overheating, abnormal noise and locking. A large amount of cooling water is sprayed for temperature reduction during production. Water vapor and cooling water easily penetrate into bearings and cause grease emulsification. Meanwhile, cooling water carries iron oxide scale dust, enters bearing cavities and acts as abrasive medium to accelerate abrasive wear of raceways. Frequent alternation of cold and heat generates thermal stress inside bearings. Ordinary steel has weak thermal fatigue resistance and easily suffers surface cracking and pitting corrosion. Frequent bearing damage requires shutdown and replacement, disrupting rolling rhythm and greatly increasing operation and maintenance costs for steel plants, becoming a key equipment pain point in the metallurgical and steel industry.

Focusing on heavy-duty transmission field of metallurgical steel industry, Japan NMT specially develops heavy-duty high-temperature water-corrosion resistant long-life cylindrical roller bearings dedicated for metallurgical steel machinery to solve industry pain points of ordinary metallurgical bearings such as insufficient load capacity, easy carbonization under high temperature, easy cooling water ingress, thermal fatigue damage and short service life. Through five core upgrades including ultra-heavy-load heat-resistant alloy steel base material, high-temperature waterproof multi-layer composite sealing, thermal fatigue resistant precision heat treatment, hydrolysis-resistant high-temperature lubrication exclusive for metallurgical conditions and alternating impact load stress optimization, it fully adapts to extreme working conditions of rolling mills and continuous casting roller tables. It fundamentally solves problems including bearing thermal fatigue damage, cooling water corrosion, high-temperature lubrication failure and impact wear, providing powerful transmission guarantee for continuous steel rolling production lines.

Core Product Advantages

1. Ultra-heavy-load heat-resistant alloy steel base material withstands impact and thermal stress: Adopting special heat-resistant alloy steel exclusively for metallurgical rolling mills with multiple forging and precision quenching & tempering heat treatments, it greatly improves matrix strength, toughness and thermal fatigue resistance. It can withstand long-term instantaneous impact heavy loads and alternating cold-hot stress during steel rolling, effectively restraining raceway spalling, component cracking and plastic deformation.

2. High-temperature waterproof multi-layer composite sealing blocks cooling water and iron oxide scale: Equipped with exclusive high-temperature resistant composite sealing structure for metallurgical conditions, it maintains stable shape under high temperature, blocks the intrusion of cooling water, steam and iron oxide dust layer by layer, avoids grease emulsification and reduces abrasive wear and internal corrosion.

3. Thermal fatigue resistant precision raceway technology delays surface damage: Adopting ultra-precision reinforced raceway grinding technology to optimize surface metallographic structure and improve high-temperature pitting resistance. Surface cracks and pitting rarely occur under repeated cold-hot alternating conditions. It maintains raceway surface precision for a long time and reduces vibration and surface defects of rolled steel products.

4. Metallurgy-specific hydrolysis-resistant high-temperature lubrication system resists coking at high temperature: Custom lubrication formula matched with high-temperature and water vapor coexisting conditions of steel rolling, featuring excellent high temperature resistance, hydrolysis resistance and anti-pollution performance. It hardly dries and carbonizes during long-time high-temperature operation, continuously forms stable protective oil film and prevents overheating locking caused by dry friction.

5. Alternating impact load optimized structure evenly disperses stress: Optimizing roller arrangement and internal clearance design to improve load distribution, relieve local stress concentration caused by instantaneous impact during steel rolling, slow down precision attenuation under long-term cyclic operation, stabilize roller system operation and guarantee surface quality of rolled steel.

Application Scenarios

Hot rolling mills, cold rolling units, continuous caster roller tables, conveying roller tables, straighteners, flying shear equipment, heating furnace auxiliary roller tables, complete sets of continuous rolling equipment for steel metallurgy.

Precision Quality Assurance

NMT heavy-duty cylindrical roller bearings for metallurgical steel industry are manufactured strictly in accordance with Japanese metallurgical heavy equipment manufacturing standards. Selected special bearing steel with heat resistance, impact resistance and cooling water corrosion resistance undergoes ultimate load durability test, high-temperature continuous temperature rise test, cooling water spray sealing test, cold-hot cycle thermal fatigue test and iron oxide dust wear resistance test. The products feature high load limit, stable heat resistance, outstanding waterproof anti-corrosion and thermal fatigue resistance, fully adapting to continuous rolling working conditions with high temperature, water vapor, dust and continuous impact heavy load in metallurgical workshops.

Product Range

Heavy-duty cylindrical roller bearings for rolling mills, high-temperature waterproof bearings for continuous casting roller tables, impact-resistant long-life bearings for cold rolling units, iron oxide scale resistant wear bearings for conveying roller tables, thermal fatigue resistant bearings for metallurgical equipment, customized non-standard ultra-heavy-load bearings for steel machinery.

Brand Strength

Japan NMT focuses on R&D and manufacturing of bearings for metallurgical steel, high-temperature water vapor and ultra-large impact heavy-load working conditions, specializing in performance optimization under environments of high-temperature thermal radiation, cooling water erosion, metal dust and alternating cold-hot cycles. With Japanese heavy industry forging and heat treatment technology, exclusive high-temperature sealing technology for metallurgical working conditions and strict extreme working condition simulation test system, it accurately solves industry problems of metallurgical bearings such as thermal fatigue cracking, cooling water corrosion, high-temperature lubrication failure and impact wear failure, supplying high-load, high-temperature resistant and ultra-long-life core transmission components for the global steel smelting and metal rolling industry.