Cylindrical roller bearings adopt parallel straight rollers matched with linear raceways. The rollers and raceways form line contact, featuring far higher radial rigidity and rated load than ball bearings as well as excellent limiting rotational speed, ideal for high-speed heavy-load rigid transmission conditions. Main structural types include NU (inner ring without ribs), NJ (single-side rib), NUP (double-side fixed ribs) and NF (outer ring rib). NJ and NUP types can bear slight unidirectional axial force for axial limiting positioning. Lubrication is compatible with circulating oil high-speed lubrication and long-life grease lubrication. Sealing options include open type, single/double-side rubber seals. Cage choices consist of solid machined brass cages, stamped steel cages and engineering plastic cages. Brass cages suit high-speed & high-temperature conditions, while steel cages are for cost-effective heavy-load applications. Widely applied to industrial gear reducers, cold & hot rolling mills, high-power motor spindles, screw air compressors, wind power gearboxes and large gear pumps, core strengths are sufficient radial rigidity, low temperature rise at high speed, strong load capacity and flexible axial positioning selection.

Main model classification: NU floating type for shaft thermal elongation compensation, NJ for unidirectional axial positioning, NUP for bidirectional axial positioning, NF outer rib positioning; Precision grades: P0 general industrial grade, P6 precision transmission grade, P4/P5 high-precision grade for rolling mills; Clearance groups: C0 standard clearance, C3 enlarged clearance for high-speed heat generation scenarios.

Performance comparison: Compared with spherical roller bearings, it delivers greatly improved high-speed performance and lower operating temperature rise without self-aligning capacity, requiring strict assembly precision for shaft coaxiality. Compared with tapered roller bearings, its higher limiting speed fits high-speed gearboxes with outstanding pure radial load capacity yet weak axial load capacity. Compared with deep groove ball bearings, radial load is increased by 3~8 times with stronger rigidity for heavy-load transmission shafts and high cost performance for pure radial service. Shortcoming: NU rib-free version cannot withstand axial load; excessive assembly coaxiality deviation easily triggers concentrated stress wear on roller edges.

Metallurgical rolling mills, heavy-duty reducers and high-speed motors run under long-term high-speed rotation, gear meshing impact, spindle thermal elongation, 24-hour full-load continuous operation and gear oil flushing lubrication. Inferior cylindrical roller bearings suffer from severe heat ablation caused by rough grinding of roller end faces and friction at high speed. Shallow hardened layers of raceways lead to pitting spalling and raceway collapse under line contact stress of heavy load. Poor rib machining accuracy causes rib corner chipping & fracture under axial force. Insufficient cage strength induces resonance fracture at high speed, roller scattering and gearbox seizure, directly resulting in gear tooth breakage of reducers, roller runout of rolling mills, motor bore burn-out and scrapping of complete transmission components, bringing huge maintenance costs for production line shutdown.

NMT cylindrical roller bearings cover full structural series of NU, NJ, NUP and NF, with sufficient stock for P4/P5 high-precision rolling mill bearings, general heavy-load reducer bearings and sealed high-speed motor bearings. Manufactured with vacuum degassed high-purity bearing steel, raceways and rollers are ultra-precision mirror grinding to reduce high-speed friction coefficient and control temperature rise. Precise chamfer modification on roller end faces eliminates edge wear induced by axial play. Differentiated rib technology features thickened reinforced ribs for positioning models to resist axial impact force. Multi-type cages match working conditions: solid brass cages ensure stable low vibration at high speed, thickened steel cages withstand impact heavy load, and nylon cages realize low noise for high-speed motors. NU floating structure compensates spindle thermal expansion to avoid thermal expansion seizure. Overall dimensions fully comply with national standards and rolling mill industry standards for direct replacement of old gearboxes and roll chocks without machining.

Metallurgical rolling and gear transmission equipment are upgraded toward higher speed, greater rigidity, lower temperature rise and longer lubrication cycle. Low-grade cylindrical roller bearings feature poor roller precision, thin raceway hardened layers and weak rib strength, leading to overheating failure and positioning failure after short-term high-speed heavy-load operation and high failure rate of transmission equipment. The market urgently needs high-speed heavy-duty cylindrical roller bearings with high-precision superfinishing, reinforced rib structure and customized structural selection for working conditions.

NMT achieves low heat generation at high speed, ultra-high radial rigidity and stable axial positioning via three core processes: precise modification of roller end faces, superfinishing of raceways and thickened reinforcement of positioning ribs. Finished bearings pass high-speed temperature rise test, radial load durability test, axial rib impact test and dimensional precision grading inspection to eliminate defective products with flawed roller contours, insufficient raceway hardness and unqualified rib strength. It guarantees continuous stable operation of rolling lines and reducer units, cutting high costs of spare parts and production suspension caused by gear damage, roll failure and motor burnout.

Core Product Advantages

Line-contact roller structure delivers strong radial rigidity and load capacity for excellent deformation resistance of rolling mills and heavy-duty gearboxes.

Diverse structural options: NU floating type compensates shaft thermal elongation; NJ/NUP realize accurate axial limit to meet various positioning demands.

Chamfer modification on roller end faces prevents edge ablation under high-speed axial play for stable temperature during long-term high-speed operation.

High-purity bearing steel with deep quenching ensures wear & fatigue resistance of raceways to avoid pitting spalling under alternating gear impact.

Optional multi-material cages for accurate matching of high-speed, heavy-load and low-noise scenarios.

Precision rib machining prevents rib edge chipping & fracture under axial force for long-lasting stable positioning.

Standardized mounting dimensions enable direct replacement for reducer, roll and motor bearing housings for convenient maintenance & assembly.

Compatible with high-speed circulating oil lubrication and long-life extreme-pressure grease lubrication for stable lubrication performance under high & low temperature conditions.

Typical Application Scenarios

High-speed shaft bearings for hard-tooth-face reducers, planetary gearboxes and wind power speed-increasing boxes; Work roll & backup roll bearings for hot rolling mills, cold rolling mills and temper mills; Spindle bearings for high-voltage high-power asynchronous motors and synchronous motors; Rotor bearings for screw air compressors and centrifugal compressors; Bearings for large gear oil pumps and shield machine reduction mechanisms; Transmission bearings for press rolls and dryer rolls of paper machines; Bearings for main cement reducers and bucket elevator gearboxes.

Quality Assurance

NMT cylindrical roller bearings adopt precision heat treatment for vacuum smelted bearing steel with high surface finish of raceways and low friction loss. Compatible with circulating gear oil and high-speed grease lubrication, operating temperature ranges from -30℃ to 130℃, adapting to harsh conditions including high-speed high temperature of rolling mills, gear impact of reducers, continuous high-speed operation of motors and temperature rise of air compressors.

Product Range

NU floating series without inner ring ribs, NJ unidirectional axial positioning series with single-side ribs, NUP bidirectional fixed series with double-side ribs, NF outer ring rib positioning series; Structure: single-row cylindrical rollers; Precision grades: P0 general grade, P6 transmission precision grade, P4/P5 high-precision grade for rolling mills; Clearance: C0 standard clearance, C3 large clearance for high speed; Sealing: open type, double-side rubber contact seal; Cages: machined brass cage, stamped steel cage, nylon resin cage.

Brand Strength

NMT Japan solves three major pain points of ordinary cylindrical roller bearings: thermal ablation of roller end faces at high speed, rib damage under axial force and roller eccentric load failure caused by coaxiality deviation. Core technologies including precise roller modification, raceway superfinishing and reinforced positioning rib structural design develop dedicated cylindrical roller bearings for rolling mills, reducers and high-speed motors. We supply bearings for reducer manufacturers, metallurgical rolling enterprises, motor manufacturers and industrial equipment maintenance service providers to enhance rigidity stability of transmission systems, extend bearing maintenance & replacement cycle and avoid economic losses from sudden breakdown of high-speed transmission equipment.