Roll support sections of hot rolling mills, cold rolling mills, temper mills, blooming mills and continuous rolling units are core transmission units of metallurgical steel production lines. They operate under harsh working conditions: ultra-large alternating combined rolling loads, continuous heat radiation from hot rolled stock, scouring by massive cooling water spray, splashing iron oxide scale dust, high-speed reciprocating operation of roll systems, dramatic temperature fluctuation and persistent axial rolling thrust. Metallurgical rolling lines demand extremely high continuity. Once bearing failure causes shutdown, it takes a long time for roll cooling and readjustment. Massive steel billets will be stranded and scrapped, leading to huge production losses. Ordinary tapered roller bearings cannot adapt to harsh environments with high temperature, water vapor and iron oxide scale in rolling mills, becoming a common pain point for iron and steel enterprises. During steel rolling, work rolls bear continuous huge radial loads and axial rolling thrust with severe load fluctuation. Ordinary bearings have insufficient fatigue resistance and are prone to raceway indentation and roller surface peeling under long-term cyclic loads, aggravating roll runout and resulting in uneven plate thickness and surface defects. Hot rolling zones receive continuous heat radiation from hot workpieces, transferring heat to bearing housings. Conventional bearings have limited heat resistance. High temperature accelerates grease oxidation and coking, easily triggering excessive temperature rise and seizure of bearings. Abundant cooling water is sprayed during production, filling the workshop with water vapor. Fine iron oxide scale dust spreads along with vapor. Simple seals cannot block impurities from penetrating into bearing cavities. Hard scale mixes with grease and forms powerful abrasive medium that rapidly wears raceways. Continuous ingress of cooling water causes grease hydrolysis and emulsification, inducing pitting and rust inside bearings. Rolling mills feature long maintenance cycles and difficult disassembly and assembly. Frequent bearing replacement continuously increases operation costs and production losses of steel plants.

Focusing on transmission supporting field for metallurgical roll supports, Japan NMT specially develops heavy-duty high-temperature & water vapor resistant tapered roller bearings dedicated for rolling mills to solve industry pain points of ordinary rolling mill bearings such as insufficient heat resistance, easy penetration of cooling water, ingress of iron oxide scale dust, susceptibility to fatigue under alternating rolling loads and short service life under continuous rolling conditions. Taking advantage of bidirectional linear load-bearing structure of tapered rollers, combined with five core upgrades including heat-resistant high-toughness special bearing steel, multi-layer labyrinth high-temperature water & scale-proof composite sealing, deep-hardening strengthening technology for raceways, high-temperature hydrolysis-resistant long-life lubrication and precise clearance matching for rolling loads, it fully adapts to harsh working conditions of ultra-large combined loads, high-temperature radiation, cooling water scouring and iron oxide scale dust for hot & cold rolling units. It fundamentally solves problems including high-temperature grease coking, water vapor rust, abrasive wear by scale and fatigue spalling, stabilizes roll rotation precision, improves plate rolling quality and guarantees long-term continuous operation of rolling lines.

Core Product Advantages

1. Bidirectional ultra-large combined load bearing withstands rolling impact and axial thrust: Adopting tapered roller linear contact structure, it bears high-strength radial loads and persistent axial rolling thrust simultaneously with uniform load distribution in contact zones. It buffers impact from rolling load fluctuation, effectively restrains excessive unilateral raceway wear caused by roll eccentric load, and stably controls axial play of roll systems.

2. Heat-resistant high-toughness special bearing steel matrix resists high-temperature fatigue spalling: Selecting heat-resistant refined bearing alloy steel specially for metallurgical rolling mills with deep quenching & tempering heat treatments to improve matrix toughness, compressive strength and pitting resistance under high temperature. It withstands long-term alternating rolling loads and effectively delays raceway fatigue damage and roller surface peeling.

3. Multi-layer labyrinth high-temperature water & scale-proof composite sealing blocks ingress of cooling water and dust: Equipped with exclusive high-temperature thickened wear lip & multi-labyrinth sealing structure for rolling mill conditions. It resists hardening and aging under high temperature, withstands continuous scouring by cooling water, intercepts iron oxide scale and water vapor layer by layer, prevents grease emulsification and failure caused by cooling water penetration, and avoids abrasive wear induced by hard scale particles entering bearing cavities.

4. Deep-hardening super-finishing technology for raceways maintains operational precision under high temperature: Deep hardening treatment plus micron-level super-finishing grinding is applied on contact surfaces of raceways and rollers to optimize contact profile, enhance dimensional stability under high temperature, reduce frictional heat generation, slow precision attenuation during long-term rolling operation and lower rolling defects on plate surfaces.

5. High-temperature hydrolysis-resistant long-life lubrication system & customized clearance matching: Internal clearance is precisely matched according to different working conditions of hot and cold rolling to avoid seizure under low temperature and seizure caused by thermal expansion at high temperature. Matched with special lubrication formula featuring high temperature resistance, hydrolysis resistance and anti-dust pollution performance, it resists high-temperature oxidation and cooling water erosion and extends online lubrication maintenance intervals of rolling mills.

Application Scenarios

Work roll and backup roll bearings for hot rolling units, roll support bearings for cold rolling units, transmission parts of temper mills, blooming mills and continuous rolling lines, heavy-duty roll support positions of bar & wire rod mills, medium plate mills and stainless steel rolling mills.

Precision Quality Assurance

NMT tapered roller bearings for metallurgical rolling mills are manufactured strictly in accordance with Japanese heavy metallurgical equipment manufacturing standards. Selected special bearing steel with heat resistance, high toughness, water vapor and wear resistance undergoes ultra-large combined load durability test, continuous high-temperature temperature rise test, cooling water spray corrosion test, iron oxide scale dust sealing test and high-low temperature cycle fatigue test. The products feature outstanding bidirectional load capacity, excellent heat resistance and reliable sealing performance against water and scale, fully adapting to 24-hour continuous rolling conditions with high-temperature radiation, cooling water spray and iron oxide scale dust in hot and cold rolling workshops.

Product Range

Heavy-duty tapered roller bearings for backup rolls of hot rolling mills, precision low-noise roll bearings for cold rolling mills, water vapor resistant long-life bearings for temper mills, dust-resistant bearings for bar and wire rod mills, four-row ultra-heavy-load tapered roller bearings specially for rolling mills, customized large-size non-standard bearings for metallurgical equipment.

Brand Strength

Japan NMT focuses on R&D and manufacturing of bearings for hot & cold rolling mills under working conditions of ultra-large combined rolling loads, heat radiation from rolled stock, cooling water scouring and iron oxide scale dust erosion, specializing in performance optimization of bidirectional load balance, high-temperature temperature rise control, water vapor sealing protection and abrasive wear prevention from hard dust. With Japanese heat-resistant high-toughness steel heat treatment technology, exclusive high-temperature water & scale-proof sealing technology for rolling mills and strict high-temperature humid working condition simulation testing system, it accurately solves industry pain points of rolling mill bearings such as high-temperature lubrication failure, rust caused by cooling water, abrasive wear failure by iron oxide scale, fatigue spalling and frequent shutdown replacement, supplying high-load, high-temperature and water vapor resistant long-life core roll support bearing components for global steel and non-ferrous metal rolling enterprises.