In the work roll bearing housings of metallurgical rolling mills, full-complement cylindrical roller bearings maintain precise roll gap control under alternating radiant heat from red-hot steel and tens of thousands of tons of rolling force. In the hoist mechanisms and rope sheaves of large cranes, full-complement cylindrical roller bearings carry hundreds of tons of lifting loads under low-speed high-torque conditions. On the drive shafts of heavy-duty gearboxes and reducers, full-complement cylindrical roller bearings transmit ultimate radial loads within limited installation space. In the intermediate bearings of ship propulsion systems, full-complement cylindrical roller bearings support reliable propeller shaft rotation under seawater corrosion and sustained heavy loads. In every piece of heavy equipment requiring ultimate radial load capacity, impact resistance and low-speed operation, full-complement cylindrical roller bearings are the optimal choice for achieving ultra-high load capacity and high-reliability transmission-



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Full-complement cylindrical roller bearings are the highest-radial-load-capacity type in the cylindrical roller bearing family. Unlike caged cylindrical roller bearings, full-complement cylindrical roller bearings eliminate cages and fill the bearing interior with the maximum number of cylindrical rollers, achieving load capacity 1.5 to 2 times that of same-size caged bearings-



. Without cages, full-complement cylindrical roller bearings have lower speed limits but offer unparalleled advantages under low-speed heavy-load and impact conditions——more rollers, uniform load distribution, strong impact resistance and simple reliable structure-



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Full-complement cylindrical roller bearings are classified into single-row and double-row types. Single-row types suit moderate radial loads and applications requiring axial displacement; double-row types double the roller quantity and load capacity, suitable for ultimate radial load applications. Based on ring configurations, they are classified into NCF type (inner ring with ribs, outer ring without ribs) and NNF type (double-row, both rings with ribs), accommodating different axial positioning and load direction requirements-



. Full-complement cylindrical roller bearings are widely used in metallurgical rolling mills, large cranes, heavy-duty gearboxes, ship propulsion systems, mining crushers, extruders, wind turbines, cement equipment, oil drilling rigs and various heavy-load low-speed and impact equipment.

NMT Full-Complement Cylindrical Roller Bearing Technology Solutions

Japan NMT full-complement cylindrical roller bearings are specialized product series developed specifically for the stringent requirements of heavy-load low-speed and impact equipment——ultimate radial load capacity, impact resistance, long life and high reliability.

Cageless Ultimate-Capacity Structural Design——Full-complement cylindrical roller bearing load capacity depends on roller quantity, diameter and length. NMT full-complement cylindrical roller bearings feature cageless design, maximizing roller quantity within limited space——roller quantity 30%-50% higher than same-size caged bearings-



. Rollers undergo precision crowning——roller generating lines feature logarithmic curve crowning eliminating edge stress concentration at roller ends, ensuring uniform load distribution along the full roller length, significantly extending bearing life under ultimate heavy loads. Bearing ring wall thickness is specially calculated and thickened to resist deformation under tens of thousands of tons of radial loads, maintaining geometric accuracy. Validated through rigorous load capacity testing, NMT full-complement cylindrical roller bearing dynamic and static load ratings reach 1.5-2 times those of same-size caged bearings.

Single-Row and Double-Row Full Coverage——NMT full-complement cylindrical roller bearings offer single-row and double-row configurations for different load requirements and installation spaces. Single-row full-complement cylindrical roller bearings (NCF type)——Single row of rollers, inner ring with ribs, outer ring without ribs, allowing axial thermal expansion displacement, suitable for moderate radial loads and axial displacement compensation applications. Double-row full-complement cylindrical roller bearings (NNF type)——Double rows of rollers with doubled roller quantity and radial load capacity, both rings with ribs for precise axial positioning, suitable for ultimate radial loads and high-rigidity applications such as rolling mill roll necks and large gearboxes-



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Precision Raceway and Roller Machining Technology——Full-complement cylindrical roller bearings have line contact between rollers and raceways, with contact quality directly determining load capacity and life. NMT full-complement cylindrical roller bearing raceways undergo precision form grinding and superfinishing, with raceway roundness, cylindricity and surface roughness strictly controlled to Ra≤0.08μm. Rollers undergo precision grinding and superfinishing, with roller diameter deviation controlled to minimal ranges, cylindricity and surface roughness strictly controlled for uniform load distribution without localized overloading. Raceway-to-roller contact stress is precisely calculated and optimized to maintain reasonable stress levels across the full load range. Precision-machined and crowned rollers and raceways fundamentally reduce friction and temperature rise during operation, significantly extending bearing fatigue life under ultimate heavy loads.

High-Strength Rib and Axial Guidance Design——Full-complement cylindrical roller bearing rollers are axially guided by ring ribs. NMT full-complement cylindrical roller bearing rib angles and dimensions are precisely calculated to provide stable guidance under axial loads and impacts. Rib-to-roller end face sliding contact surfaces are optimized——rib tilt angles are precisely matched, roller end faces are precision-ground and polished for low friction and high reliability under axial thrust. Rib materials undergo specialized heat treatment for excellent surface hardness and wear resistance, effectively resisting roller end face wear and scoring under axial impacts. Validated through rigorous axial load and impact testing, NMT full-complement cylindrical roller bearing ribs maintain geometric integrity and guidance accuracy under repeated axial impacts.

Impact and Fatigue Resistance Enhanced Design——Full-complement cylindrical roller bearings endure severe impact loads in rolling mills, crushers and similar equipment. NMT full-complement cylindrical roller bearing roller and raceway materials undergo specialized heat treatment processes, achieving extremely high surface hardness (HRC60-64) while maintaining core toughness to effectively resist indentation and spalling under impact loads. Bearing ring wall thickness is specially calculated and thickened to resist deformation under impact loads, maintaining geometric accuracy. Roller end face-to-rib contact areas are lubrication-optimized for adequate lubrication and heat dissipation under impact conditions. Validated through rigorous impact fatigue testing, NMT full-complement cylindrical roller bearings show no indentation or spalling on raceways or roller surfaces under simulated rolling mill and crusher impact cycles, maintaining stable rotational accuracy-



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Cageless High-Reliability Structure——Full-complement cylindrical roller bearings eliminate cages, fundamentally eliminating cage fracture, wear and guidance failure risks. NMT full-complement cylindrical roller bearings have minimal clearances between rollers (typically 0.5-2mm), ensuring rollers do not contact each other during operation. The cageless structure reduces component count and simplifies structure, lowering manufacturing and assembly complexity and improving bearing reliability in harsh environments. Full-complement cylindrical roller bearings have stronger survival capability than caged bearings under poor lubrication, dust ingress and other harsh conditions, particularly suitable for rolling mills, mining machinery and other equipment with limited maintenance access-



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Heavy-Load Lubrication and Seal Design——Full-complement cylindrical roller bearings under ultimate heavy-load and impact conditions impose very high requirements on grease extreme-pressure performance and retention. NMT full-complement cylindrical roller bearings are pre-filled with specialized grease formulated with high-viscosity synthetic base oils and extreme-pressure anti-wear, rust-preventive additives, forming stable lubricating films under ultimate radial loads and impacts to effectively separate roller and raceway contact surfaces. Grease features excellent water washout resistance and dust contamination resistance, resisting emulsification, bleed-out and hardening in harsh environments. Bearings employ high-performance contact rubber seals or labyrinth seals——contact rubber seals effectively block external dust, moisture and contaminant ingress; labyrinth seals suit ultra-large bearings and high-temperature applications. Seal materials utilize wear-resistant, mud-resistant, temperature-resistant specialty rubber formulations, maintaining long-term elasticity and sealing performance in harsh environments.

Low-Speed and Oscillation Adaptability——Full-complement cylindrical roller bearings typically operate under low-speed rotation or limited-angle oscillation. NMT full-complement cylindrical roller bearings optimize grease rheological properties and bearing internal geometry to maintain stable lubricating films and low-friction characteristics during low-speed oscillation. Roller end face-to-ring rib sliding contact surfaces undergo specialized surface treatment to reduce friction coefficients and wear rates under low-speed oscillation. Bearings undergo low-speed oscillation durability testing, maintaining stable performance with low friction and low temperature rise under simulated crane hoisting, mill reversing and other frequent start-stop and limited-angle oscillation conditions.

Comprehensive Product Range——NMT full-complement cylindrical roller bearings offer diverse product ranges for different application scenarios and load requirements. NCF type single-row full-complement cylindrical roller bearings——Inner ring with ribs, outer ring without ribs, allowing axial displacement for moderate heavy loads and thermal expansion compensation applications. NNF type double-row full-complement cylindrical roller bearings——Double rows of rollers with doubled load capacity, both rings with ribs for ultimate radial loads and high rigidity applications-



. SL type full-complement cylindrical roller bearings——Designed for cranes and large gearboxes with convenient installation and removal-



. Full-complement cylindrical roller bearing assemblies——Roller and cage assemblies without outer or inner rings for extremely space-constrained applications-



. All product ranges are available in standard sizes and custom designs, with NMT providing precise bearing selection and design recommendations based on specific load, speed, temperature and environmental conditions.

Why Choose NMT Full-Complement Cylindrical Roller Bearings?

Compared to conventional caged bearings and industry-standard full-complement cylindrical roller bearings, NMT full-complement cylindrical roller bearings offer distinct advantages:

• Cageless structure for maximized roller quantity, load capacity 1.5-2 times caged bearings-



• Single-row (NCF) and double-row (NNF) full coverage for different load requirements-



• Precision logarithmic curve roller crowning eliminating edge stress concentration

• Superfinished rollers and raceways with Ra≤0.08μm

• Specialized heat treatment for surface HRC60-64 with tough core

• Thickened ring walls for deformation resistance under ultimate heavy loads

• High-strength rib optimization and precision-ground roller end faces for axial impact resistance

• Cageless structure eliminating cage fracture and wear risks-



• High-viscosity extreme-pressure anti-wear rust-preventive grease for stable oil films under ultimate loads

• Contact rubber seals/labyrinth seals dual options for dust and moisture protection

• Low-speed oscillation adaptability for stable low-friction frequent start-stop

• Passed load, impact, rib strength and low-speed durability testing

These performance advantages establish NMT full-complement cylindrical roller bearings as the core precision components for metallurgical rolling mills, large cranes, heavy-duty gearboxes, ship propulsion systems, mining crushers and various heavy-load low-speed drive equipment.

Application Scenarios

Metallurgical rolling mill work roll and backup roll bearings

Large crane hoist mechanisms and rope sheave bearings

Heavy-duty gearboxes and reducers bearings

Ship propulsion system intermediate bearings

Mining crushers and vibrating screen bearings

Extruders and presses bearings

Wind turbine main shaft bearings

Cement rotary kilns and coolers bearings

Precision Manufacturing

Produced strictly according to ISO precision standards and full-complement cylindrical roller bearing manufacturing specifications, with zero-defect quality execution, NMT full-complement cylindrical roller bearings utilize high-purity bearing steel, processed through vacuum degassing treatment, precision heat treatment, raceway precision form grinding and superfinishing, precision roller crowning and screening/grouping, ring rib precision machining, optional seal precision assembly, specialized extreme-pressure grease precision filling, rotational accuracy inspection, load capacity testing, impact testing, rib strength testing, low-speed oscillation durability testing and seal performance testing. Every product is processed through fully automatic grinding and superfinishing in temperature-controlled clean workshops, with critical dimensional tolerances strictly controlled—ensuring ultimate load capacity, impact resistance and long-life reliability.

Product Range

NCF type single-row full-complement cylindrical roller bearings

NNF type double-row full-complement cylindrical roller bearings

SL type full-complement cylindrical roller bearings

Full-complement cylindrical roller bearing assemblies

High-precision full-complement cylindrical roller bearings

Heavy-load full-complement cylindrical roller bearings

Custom non-standard full-complement cylindrical roller bearings

Global Industrial Service

Japan NMT supplies high-quality full-complement cylindrical roller bearings to global metallurgical equipment manufacturers, crane machinery companies, gearbox producers and heavy industrial users. With ultimate-capacity impact-resistant precision engineering and long-term stable reliable performance, NMT continuously empowers ultimate load capacity and reliable operation of global heavy-load low-speed drive equipment.