Heavy-duty equipment such as industrial robot reducers, construction machinery travel mechanisms, metallurgical rolling mills, mining crushers and large gearboxes are subjected to large radial loads and frequent impact loads during operation. Installation space is often limited, requiring bearings to provide maximum radial load capacity within the smallest possible cross-section. Conventional cylindrical roller bearings with cages have limited roller quantity and size due to cage space occupation, restricting load capacity. Increasing bearing external dimensions to compensate for insufficient capacity would add weight and require more installation space.

 

Most heavy-duty equipment operates under low-speed heavy-load conditions with frequent start-stop, impact and vibration coexistence. Cages are prone to deformation or fracture under alternating loads and impact. Once the cage fails, rollers lose constraint, collide and挤压 each other, leading to rapid bearing damage. The industry urgently requires bearings with maximum roller quantity, ultimate load capacity, no cage requirement, and the ability to withstand heavy loads and impacts.

 

NMT Full-Complement Cylindrical Roller Bearings employ a cage-free design, accommodating the maximum number of rollers within the same external dimensions. Roller quantity increases by 30% to 50% compared to caged bearings of the same size, with significantly enhanced radial load capacity. Rollers and raceways form line contact with loads evenly distributed along the contact generatrix, suitable for heavy loads and impact loads. Micro-protrusions on roller end faces effectively reduce friction and wear between rollers.

 

Rollers are precision-machined from high-purity bearing alloy steel, subject to strict micron-level dimensional sorting, with surfaces superfinished for low friction coefficient and minimal temperature rise. Inner and outer rings undergo forging, precision grinding and superfinishing. All components receive carburizing quenching heat treatment and long-term low-temperature stabilization processing to achieve sufficient surface hardness with core toughness, balancing wear resistance and impact resistance. Multiple structural types are available——N type (inner ring without ribs), NU type (outer ring without ribs), NJ type (inner ring with single rib), NUP type (inner ring with single rib and retaining ring)——adapting to different axial positioning requirements.

 

Products adopt international standard dimensions with excellent interchangeability. Comprehensive specifications cover bore diameters from 20mm to over 400mm, widely applied to industrial robot reducers, construction machinery travel mechanisms, metallurgical rolling mills, mining crushers, large gearboxes and various heavy-duty equipment. The bearings adapt to low-speed heavy-load, frequent start-stop, impact and vibration coexistence conditions.

 

Core Product Advantages

 

Cage-free full-complement roller design increases roller quantity by 30% to 50% compared to caged bearings of the same size, maximizing radial load capacity;

 

Line contact between rollers and raceways with loads evenly distributed along the contact generatrix, suitable for heavy loads and impact loads;

 

Micro-protrusions on roller end faces effectively reduce friction and wear between rollers, preventing mutual挤压;

 

Precision carburizing quenching heat treatment across all components provides high surface hardness with good core toughness, resisting wear and impact;

 

Superfinished raceways matched with graded rollers deliver low friction torque and minimal temperature rise for low-speed heavy-load continuous operation;

 

Cage-free design eliminates cage deformation and fracture risks for higher reliability;

 

Multiple structural types available (N, NU, NJ, NUP types) for flexible adaptation to different axial positioning requirements;

 

Standard external dimensions ensure great interchangeability to replace imported counterparts and lower procurement costs.

 

Typical Application Scenarios

 

Industrial robot reducers (RV reducers, planetary reducers); Construction machinery travel mechanisms and track drive wheels; Metallurgical rolling mill backup rolls and work rolls; Mining crushers and vibrating screens; Large gearboxes and transmissions; Marine propulsion systems and steering gears; Wind turbine gearboxes and main shaft supports; Presses and heavy forging equipment.

 

Quality Assurance

 

NMT Full-Complement Cylindrical Roller Bearings are manufactured with premium refined bearing alloy steel. Incoming inspection includes chemical composition testing and metallurgical sampling inspection to eliminate material defects at source. Roller blanks are processed by precision rolling and cutting, followed by sequential rough grinding, finish grinding and superfinishing with strict control over roller profile precision, crowning parameters and surface roughness. Stress relief annealing is conducted after rough machining of inner and outer ring forgings to eliminate internal stress, followed by carburizing quenching and low-temperature stabilization treatment to reduce dimensional variation risks under long-term heavy loads.

 

All rollers pass flaw detection screening to remove parts with cracks and dents. All components go through high-pressure cleaning and dust-free drying before assembly in clean workshops. Appropriate grease is filled according to practical operating conditions and lubrication methods. After assembly, finished bearings undergo radial load endurance testing, impact load inspection, temperature rise testing and rotational accuracy inspection. All unqualified products are eliminated completely to guarantee stable and consistent performance of bulk goods and supply reliable full-complement roller bearing solutions for heavy-duty equipment.

 

Product Range

 

Full-complement cylindrical roller bearing standard series (N type, NU type, NJ type, NUP type); Bore diameters from 20mm to over 400mm; Full-complement roller structure; Copper alloy and steel cage options available (for某些 models).

 

Brand Strength

 

NMT focuses on R&D and manufacturing of heavy-duty full-complement cylindrical roller bearings. Targeting common industry challenges of large radial loads, impact conditions, compact spaces and cage-free reliability in industrial robot reducers, construction machinery and metallurgical equipment, NMT continuously optimizes roller crowning, end face contact conditions and carburizing heat treatment technology. The bearings effectively solve common problems of caged bearings such as limited roller quantity for insufficient capacity and cage deformation and fracture under impact. NMT products reduce risks of bearing failure on heavy-duty equipment, improve long-term operational stability and reliability, and support stable continuous operation of various heavy-duty equipment.