Core steelmaking and metallurgical equipment including hot rolling mills, cold rolling mills, continuous casters, roller tables, straighteners and coilers operate under extreme workshop conditions: continuous ultra-large alternating rolling impact loads, high-temperature heat radiation from steel billets, splashing hard iron scale, circulating cooling water spray, drastic alternating cold and hot temperature and uninterrupted 24-hour rolling production. Steel production lines demand extremely high continuity. Sudden bearing failure directly causes roll vibration, uneven plate thickness and surface scratches. In severe cases, full-line shutdown occurs. Steel billets cool down and cannot be further processed, requiring long restart time and resulting in massive output and raw material losses. Ordinary cylindrical roller bearings cannot withstand harsh metallurgical site conditions and have become a common pain point for steel plants. During steel rolling, rolls bear huge extrusion and periodic impact loads. Ordinary bearing materials lack sufficient fatigue resistance and tend to form raceway indentation and surface peeling under long-term cyclic stress, leading to roll runout, wave defects and thickness deviation on steel plates. Steel billets in hot rolling zones reach extremely high temperatures and continuously transfer heat to bearing positions. Conventional bearings have limited heat resistance. Long-term high temperature accelerates grease oxidation, coking and drying failure, easily triggering bearing overheating and seizure. Hard iron scale fragments continuously fall off during production. With high hardness and strong abrasiveness, fine scale particles penetrate into bearings through simple seals, mix with grease to form abrasive medium and rapidly wear raceways and rolling elements. Continuous caster and roller table areas are sprayed with cooling water. Water vapor mixed with scale forms mud, invades bearing cavities and induces rust and pitting wear. Equipment undergoes frequent cold-hot alternation leading to repeated condensation inside bearings and further accelerated corrosion. Maintenance procedures for metallurgical equipment are complicated and shutdown losses are huge. Frequent bearing replacement continuously increases operation and maintenance costs of steel plants.

Focusing on transmission supporting field for metallurgical steel rolling industry, Japan NMT specially develops ultra-heavy-load high-temperature scale-resistant wear-resistant long-life cylindrical roller bearings dedicated for metallurgical and steel machinery to solve industry pain points of ordinary metallurgical bearings such as insufficient load capacity, easy failure under high temperature, easy ingress of iron scale, vulnerability to cooling water rust and short service life under continuous rolling conditions. Through five core upgrades including heat-resistant ultra-high-strength alloy steel base material, multi-layer scale-proof high-temperature labyrinth composite sealing, surface anti-corrosion strengthening heat treatment for raceways, wide-temperature hydrolysis-resistant long-life high-temperature lubrication and rolling alternating load stress equalization optimization, it fully adapts to harsh working conditions of hot & cold rolling mills, continuous casters and roller tables with heavy loads, high temperature, solid impurities and cooling water erosion. It fundamentally solves problems including bearing impact fatigue damage, scale abrasion, high-temperature lubrication failure and cooling water corrosion, stabilizes roll operation precision and guarantees rolling quality of plates and sections.

Core Product Advantages

1. Heat-resistant ultra-high-strength alloy steel matrix withstands continuous heavy rolling impact loads: Adopting high-purity heat-resistant alloy steel specially for metallurgical rolling mills with multiple deep quenching & tempering strengthening heat treatments to greatly improve structural toughness, compressive strength and fatigue resistance under high temperature. It bears long-term huge alternating extrusion and impact loads of rolls, effectively restraining raceway plastic deformation, fatigue peeling and component cracking.

2. Multi-layer scale-proof labyrinth composite sealing blocks ingress of scale and cooling water: Equipped with exclusive multi-layer labyrinth and high-temperature wear-resistant lip sealing system for metallurgical working conditions. It resists aging and deformation under high temperature, intercepts hard iron scale fragments layer by layer and prevents penetration of cooling water spray. It avoids formation of abrasive paste mixed by scale impurities and grease and lowers risks of internal abrasive wear and grease emulsification failure.

3. Surface anti-corrosion strengthening heat treatment for raceways improves pitting and wear resistance: Surface hardening strengthening treatment is applied on raceways and rolling elements to optimize metallographic structure, enhance surface hardness, pitting resistance and spalling resistance. It effectively slows precision attenuation under continuous scale abrasion and alternating cold-hot corrosion and extends bearing service life.

4. Wide-temperature hydrolysis-resistant long-life high-temperature lubrication system withstands cooling water scouring: Custom lubrication formula developed for metallurgical high-temperature and water spray conditions features excellent high-temperature oxidation resistance, hydrolysis resistance and wash resistance. It hardly cokes and dries at high temperature and resists emulsification and deterioration when contacting cooling water, maintains stable high-temperature protective oil film for a long time and extends lubrication maintenance intervals.

5. Optimized structure for alternating rolling loads evenly disperses impact stress: Optimizing roller arrangement and internal clearance matching to improve load distribution, relieve local stress concentration caused by continuous impact during rolling, slow precision loss from long-term continuous operation, stabilize smooth roll operation and reduce surface defects on steel plates.

Application Scenarios

Hot rolling mills, cold rolling mills, thin plate rolling mills, continuous casters, roller tables, straighteners, coilers, uncoilers, temper mills, roll supporting and transmission parts of various section steel and steel plate rolling production lines.

Precision Quality Assurance

NMT heavy-duty cylindrical roller bearings for metallurgical and steel machinery are manufactured strictly in accordance with Japanese metallurgical equipment manufacturing standards. Selected special bearing steel with heat resistance, impact resistance, scale wear resistance and cooling water corrosion resistance undergoes ultimate rolling load durability test, iron scale sealing protection test, continuous high-temperature temperature rise test, cooling water spray corrosion test and cold-hot cycle fatigue test. The products feature high load limit, stable heat resistance, outstanding scale-proof sealing performance and excellent wear & corrosion resistance, fully adapting to 24-hour continuous heavy-load rolling conditions with high temperature, splashing hard scale and cooling water scouring in steel workshops.

Product Range

High-temperature heavy-duty cylindrical roller bearings for hot rolling mills, high-precision long-life bearings for cold rolling mills, waterproof scale-resistant bearings for continuous casters, impact-resistant wear-resistant bearings for roller tables, low-vibration precision bearings for straighteners and coilers, customized non-standard ultra-heavy-load bearings for metallurgical rolling equipment.

Brand Strength

Japan NMT focuses on R&D and manufacturing of bearings for heavy metallurgical steel rolling under working conditions of high-temperature billet radiation, hard iron scale, cooling water corrosion and continuous alternating rolling loads, specializing in performance optimization under scenarios of high-temperature radiation, solid particle abrasion, alternating cold and hot temperature and continuous impact loads. With Japanese heat-resistant special steel heat treatment technology, exclusive multi-layer scale-proof high-temperature sealing technology for metallurgy and strict extreme working condition simulation testing system, it accurately solves industry problems of metallurgical bearings such as abrasive wear caused by scale, high-temperature coking seizure, cooling water rust, impact fatigue damage and frequent maintenance replacement, supplying high-load, high-temperature resistant and solid-impurity abrasion resistant long-life core transmission components for global plate, section steel and special steel smelting & rolling industries.