Ball mills, rotary dryers, roller presses, ore crushers and sintering machines are core large-scale main machines in mining, metallurgy, cement and building materials industries. Bearing support positions operate under harsh long-term conditions: ultra-large combined alternating radial and axial heavy loads, violent vibration induced by material impact, deflection of long transmission shafts, coaxial deviation caused by frame deformation under load, extremely high dust concentration on site, hard particles mixed into lubricating oil and 24-hour non-stop continuous operation. Ordinary roller bearings have no self-aligning capability. Slight shaft bending results in unilateral loading of rolling elements and rapid edge stress concentration and fatigue spalling. Failure of main bearings triggers shutdown and maintenance of the whole production line, leading to massive production losses and high maintenance costs. Conventional bearings cannot simultaneously satisfy the three major demands of heavy load, impact resistance and misalignment compensation, which has long troubled operation teams of mines, cement plants and metallurgical enterprises.

Focusing on R&D and manufacturing of heavy-duty transmission bearings for mining and metallurgy, Japan NMT launches heavy-duty spherical roller bearing series to solve industry pain points of traditional models including roller edge spalling under impact loads, severe abrasive wear in dusty environments, excessive temperature rise under heavy loads and vulnerable cages under shock. Adopting classic structure of double-row symmetric spherical rollers and outer ring spherical raceway, combined with five core upgrades including high-purity vacuum degassed bearing steel, precision crown profiling on roller ends, high-strength stamped/solid cages, optimized internal load distribution design and clearances adapted to wide working conditions, the series combines powerful combined load capacity and excellent self-aligning performance. Limited angular tilt between shaft and housing is permitted. Widely equipped for ball mills, crushers, roller presses and rotary equipment, the bearings disperse contact stress, resist impact wear and greatly extend service life of bearings for large heavy machinery.

Core Product Advantages

1. Integrated ultra-high combined load capacity & self-aligning function adapting to shaft deflection and frame deformation: Spherical outer raceway matched with double-row spherical rollers delivers huge radial and bidirectional axial load capacity. It allows angular deflection of shaft relative to housing, compensating long shaft bending and assembly misalignment, avoiding unilateral eccentric loading of rolling elements and fundamentally reducing eccentric spalling failures.

2. Outstanding impact and vibration resistance suitable for crushing and grinding impact conditions: Double-row line-contact roller bearing structure provides sufficient effective bearing area. It continuously sustains material impact and alternating start-stop loads, buffering stress fluctuations caused by violent vibration, ideal for harsh applications with drastic load fluctuation such as crushers and ball mills.

3. Precision roller crowning relieving edge stress concentration under heavy loads: Optimized curved profiling on both roller ends eliminates peak edge stress under tilted and heavy-load conditions, restrains edge pitting and premature spalling and markedly improves contact fatigue life under alternating impact loads.

4. Stable material and heat treatment resisting abrasive wear in dusty environments: Premium high-purity vacuum degassed bearing alloy steel undergoes deep hardening and stabilized tempering for uniform and stable metallographic structure and sufficient surface hardness, slowing abrasive wear caused by dust particles mixed in lubricant and extending service life under severe conditions.

5. Multiple structural and cage options for flexible selection: Two bore types available: cylindrical bore and tapered bore; stamped steel cages and solid brass cages optional; full range of standard C0, C3, C4 enlarged clearances; sealed variants for partial sizes to block dust ingress, suitable for open harsh production sites.

Application Scenarios

Main support bearings for horizontal ball mills in cement and mining industry; support roller bearings of rotary dryers and rotary kilns; auxiliary drive bearings for cement roller presses and vertical mills; main shaft bearings for jaw crushers, cone crushers and hammer crushers; large drive drum bearings for sintering machines and belt conveyors; supporting positions of metallurgical sintering equipment and heavy roller tables.

Precision Quality Assurance

NMT spherical roller bearings are manufactured strictly in accordance with Japanese heavy industrial bearing standards. Raw materials are inspected one by one via ultrasonic flaw detection. Tests including continuous heavy-load durability test, fatigue test under tilted self-aligning condition, impact vibration durability test, dust abrasive wear simulation test and hot-cold cycle dimensional stability test are carried out. Featuring sufficient load capacity, reliable self-alignment and excellent impact & wear resistance, the bearings fully adapt to all-weather continuous heavy-duty operation of large main machines in mining, metallurgy and building materials sectors.

Product Range

222,223,230,231,232,240,241 series spherical roller bearings; cylindrical bore & tapered bore; stamped steel cages, solid brass cages; open type & sealed type; standard C0, C3, C4 clearance; complete standard sizes, customized large-size non-standard specifications available.

Brand Strength

Japan NMT focuses on R&D and manufacturing of heavy-duty spherical roller bearings, specializing in core technologies including spherical roller profile optimization, contact stress simulation analysis, stabilized heavy-duty heat treatment and precision machining & inspection for large-size bearings. Supported by complete heavy-load impact simulation laboratories and automatic heavy-duty heat treatment production lines, NMT solves common industry pain points such as eccentric spalling, dust abrasion and insufficient impact life of bearings used in ball mills, crushers and roller presses, supplying high-load, impact-resistant and long-life spherical roller bearing solutions for global mining, metallurgical and building materials machinery manufacturers.