Cylindrical roller bearings adopt linear contact structure of cylindrical rollers. The line contact between rollers and raceways brings extremely strong radial load capacity and excellent limiting speed performance. According to rib structure, they are divided into NU (no inner ring rib), NJ (single-side rib), NUP (locatable), NF (outer ring rib) and other configurations, which can realize slight axial sliding to compensate thermal elongation of shafts. Single-side rib versions can bear minor axial positioning force. Featuring high overall rigidity, excellent heat dissipation and good alternating load resistance, they are available in single-row, double-row and four-row structures with both open and sealed types. Compatible with circulating thin oil lubrication and long-term grease lubrication, they are widely applied to high-power motors, steel rolling equipment, industrial gearboxes, fans, air compressor main shafts and other high-speed heavy-load equipment dominated by radial force, serving as main supporting bearings for high-power rotating machinery.

Main model classification: NU2000/NJ2000 single-row general series, NU3000 heavy-duty reinforced series, N2000 compact series, NN double-row series, FC four-row heavy-duty rolling mill special series. Structural forms: NU floating type, NJ unidirectional axial positioning, NUP bidirectional simple positioning. Sealing forms: open type, 2RS rubber dust-proof sealed type. Precision grades: P0 industrial grade, P6 transmission precision grade, P5 high-speed motor grade, P4 high-precision rolling mill grade.

Performance comparison: Compared with deep groove ball bearings, radial load capacity is several times higher with stronger rigidity for heavy-load scenarios, yet no axial load bearing capacity. Compared with tapered roller bearings, it has obvious advantages in high-speed performance and lower temperature rise, no requirement for forced axial preloading and simple assembly. Compared with spherical roller bearings, rotational accuracy and limiting speed are higher without self-aligning function, requiring good concentricity of the shaft. Shortcoming: Standard NU type cannot bear axial force, so positioning bearings shall be matched for shafting; deviation of shaft concentricity easily causes stress concentration and wear at roller edges.

High-voltage variable-frequency motors, hot/cold rolling rolls, speed-increasing gearboxes, large centrifugal fans and screw air compressor main shafts operate under high-speed rotation, high-power radial load, thermal expansion during operation and circulating lubricant conditions with continuous alternating stress. Inferior cylindrical roller bearings suffer from uneven roller dimensional tolerance leading to local indentation under uneven force. Insufficient quenching hardness of ribs causes rib corner cracking under axial play. Rough grinding texture of raceways accelerates temperature rise during high-speed friction and carbonization failure of grease. Insufficient cage strength triggers vibration and deformation at high speed, directly resulting in abnormal noise & rotor scraping of motors, thickness deviation of rolling mill rolls, bearing seizure of gearboxes and excessive vibration shutdown of fans, bringing huge losses for continuous industrial production lines.

NMT cylindrical roller bearings cover full specifications of single-row, double-row and four-row types including NU, NJ, NUP, NN and FC series with sufficient stock for floating type, positioning type and sealed dust-proof type. Four-row rolling mill bearings can be customized for clearance on demand. Manufactured from high-purity vacuum degassed bearing steel with integral quenching and tempering stabilization treatment. Super mirror finishing is applied to raceways and rollers, and chamfer modification at roller ends eliminates edge load concentration. Two optional cage structures: solid copper cage for low vibration & noise under high-speed conditions and stamped steel cage for heavy-load cost performance. Reinforced quenching is adopted for ribs of NJ and NUP positioning bearings to resist impact from axial play. 2RS sealed versions use oil-resistant nitrile rubber seals to block intrusion of moisture and dust. All dimensions comply with national standards for direct replacement of domestic and imported bearings of the same specification during motor maintenance, rolling mill upkeep and gearbox overhaul without machining of bearing housings.

High-power power motors, metallurgical rolling production lines, high-speed gear transmission and large-scale wind power ventilation equipment are upgraded toward high speed & low noise, long service life under heavy load, thermal expansion compensation and extended maintenance cycle. Ordinary low-grade cylindrical roller bearings have poor roller precision, insufficient raceway finish and weak rib wear resistance, leading to rapid pitting corrosion, overheating and rib breakage under high speed & heavy load. They cannot meet operating requirements such as 24-hour continuous operation of variable-frequency motors, non-stop rolling of rolling mills and stable outdoor operation of fans all year round. The market urgently needs cylindrical roller bearings with high precision, high rigidity and adaptability to axial thermal expansion sliding.

NMT realizes uniform load distribution, low temperature rise at high speed and smooth axial sliding via three core processes: precision grouping and matching of rollers, super-finishing of raceways and reinforced quenching of ribs. All finished bearings pass radial clearance sorting, runout inspection and high-speed temperature rise simulation test to eliminate defective products with out-of-tolerance dimensions, surface defects and poor heat treatment. It stabilizes radial rigidity of the main shaft, relieves stress from shaft thermal elongation and extends the overall service life of bearings.

Core Product Advantages

Linear contact cylindrical roller structure delivers ultra-large radial load capacity, high rigidity and excellent heat dissipation during high-speed rotation.

Diverse rib structure options: NU floating type compensates thermal elongation of shafts; NJ/NUP realize axial positioning to adapt to various shaft layouts.

Full coverage of single-row, double-row and four-row structures: single-row for high-speed motors, four-row FC exclusively for extreme heavy load of rolling mills.

Roller end modification eliminates edge stress concentration and greatly reduces failure rate of eccentric load wear.

Dual cage options of copper and steel plate: copper cage for noise & vibration reduction at high speed, stamped steel cage for higher cost performance under heavy load.

Optional 2RS sealing structure allows direct grease lubrication without complex oil circuit machining of the box body.

High-purity bearing steel resists fatigue spalling for long-term continuous alternating load industrial operation.

Standard overall dimensions offer strong universal interchangeability for convenient replacement during equipment maintenance.

Typical Application Scenarios

Support bearings at both ends of high-voltage asynchronous motors, variable-frequency spindle motors and explosion-proof motors; four-row roll bearings for hot rolling mills, cold rolling mills and temper mills; input & output bearings for wind power speed-increasing boxes and industrial hard-tooth surface gearboxes; main shaft bearings for large centrifugal induced draft fans, boiler fans and cooling tower fans; crankshaft support bearings for screw air compressors and piston compressors; heavy-duty support bearings for paper machine rollers, cement roller presses and conveying roller tables.

Quality Assurance

NMT cylindrical roller bearings are made of vacuum refined bearing steel to reduce internal inclusions and improve fatigue life. Mirror finishing of raceways and rollers lowers friction coefficient for gentle temperature rise during high-speed operation. High-frequency quenching strengthens positioning bearing ribs for enhanced impact resistance. Compatible with circulating thin oil lubrication and long-life lithium grease lubrication, operating temperature ranges from -30℃ to 135℃, adapting to closed motor cavities, high-temperature oil pools of rolling mills and dusty & humid outdoor fan environments.

Product Range

NU/NJ/NUP/NF single-row cylindrical roller bearings, NN double-row precision cylindrical roller bearings, FC four-row heavy-duty bearings dedicated for rolling mills; Structures: floating type, unidirectional positioning, bidirectional positioning; Sealing: open type, 2RS double-sided rubber seal; Precision grades: P0, P6, P5, P4 high-precision grade.

Brand Strength

NMT Japan solves three major pain points of conventional cylindrical roller bearings: uneven load caused by poor roller precision, excessive temperature rise at high speed and easy fracture failure of positioning ribs. Three core technologies including roller grouping & matching, super-finishing of raceways and reinforced heat treatment of ribs deliver cylindrical roller bearings with high rigidity, stable high-speed operation and reliable axial thermal compensation. We supply bearings for motor manufacturers, metallurgical rolling enterprises, gearbox manufacturers, fan equipment manufacturers and industrial equipment maintenance providers to stabilize operating conditions of high-speed heavy-load equipment, reduce unexpected shutdown caused by bearing faults and cut operation & maintenance costs of production lines.