In the core transmission system of industrial and collaborative robots, joint bearings directly determine the overall machine's motion accuracy, dynamic response, and load capacity. Traditional bearing combination schemes have loose structures and occupy large spaces, making it difficult to meet the compact and lightweight design requirements of modern robot joints. Meanwhile, under working conditions such as high-speed start-stop and heavy-load grasping, robot joints are subjected to complex composite loads including radial, axial, and overturning moments. Ordinary bearings are highly susceptible to eccentric loading, clearance expansion, and precision degradation, leading to mechanical arm jitter and positioning inaccuracy. Equipment manufacturers urgently need a precision bearing capable of achieving omnidirectional high-rigidity load-bearing within an extremely small cross-section to break through the physical limits of robot joint design.

With the rapid rise of new intelligent equipment such as humanoid robots and collaborative robots, robot joints face even more stringent challenges for bearings. They are required not only to possess micron-level rotational accuracy and zero backlash but also to maintain ultra-low friction torque and silent performance during frequent forward and reverse oscillations. Traditional bearings are prone to deformation under complex moments, and the cumulative errors caused by multi-bearing combinations severely weaken the overall repeatability positioning accuracy. Furthermore, collaborative robots operating alongside humans have extremely high requirements for operational smoothness and low noise. The market urgently demands a cross roller bearing solution customized for robot joints that balances extreme compactness with ultra-high rigidity.

NMT Precision Cross Roller Bearings are born to conquer the complex load challenges of robot joints. The internal structure of this series features cylindrical rollers arranged in a 90-degree vertical cross pattern on V-shaped raceways, enabling a single bearing to simultaneously withstand composite loads from radial, axial, and overturning moments. This integrated load-bearing design completely eliminates the structural looseness of traditional combined bearings, increasing rigidity by 3 to 4 times compared to conventional bearings. Meanwhile, NMT compresses the bearing cross-section to the extreme, providing ultra-strong support while freeing up precious space for internal wiring, sensor integration, and motor miniaturization, perfectly adapting to various lightweight and integrated robot joint designs.

In precision manufacturing, NMT exercises nearly obsessive precision control over every component of its cross roller bearings. The bearing rings and raceways undergo nano-level super-finishing, with geometric precision controlled at the micron level; precision rollers undergo strict size and weight sorting to ensure absolutely uniform load distribution. NMT's unique preload management technology accurately eliminates internal micro-clearance, ensuring the bearing maintains constant rigidity during high-speed reciprocating motions of robots, completely eliminating trajectory deviations and bringing the robot's repeatability positioning accuracy to the industry's top level. Additionally, optimized streamlined rollers and low-friction cage designs significantly reduce running resistance and noise, endowing collaborative robots with a silky-smooth interactive experience.

With rich specifications, these bearings are widely used in the waist, upper arm, elbow, and wrist joints of six-axis industrial robots, rotation axes of collaborative robots, core support parts of harmonic and RV reducers, as well as high-end equipment such as precision rotary tables and semiconductor manufacturing equipment, satisfying the supporting needs of various high-precision, high-rigidity transmission nodes.

Core Product Advantages

Rollers arranged in a 90° vertical cross pattern; a single bearing withstands composite loads of radial, axial, and overturning moments, offering excellent omnidirectional load capacity;

Integrated compact design increases rigidity by 3-4 times compared to traditional bearings, completely eliminating joint jitter and eccentric deformation;

Ultra-thin cross-section greatly saves joint installation space, facilitating overall robot lightweighting and high internal integration;

Micron-level super-finishing and strict preload management achieve zero backlash and ultra-high rotational accuracy, ensuring precise repeatability positioning;

Streamlined rollers and low-friction cage design result in ultra-low running torque, smooth and stutter-free motion, meeting micro-operation needs;

Low-noise operation, combined with high-precision fitting, provides a quiet and smooth human-robot interaction experience for collaborative robots;

Premium high-purity steel and special heat treatment offer excellent fatigue and wear resistance, easily handling high-frequency oscillation and heavy-load impacts;

Coexistence of standardization and customization, flexibly adapting to the joint structures of various industrial robots, collaborative robots, and precision turntables.

Typical Application Scenarios

Joints of six-axis industrial robots; Support for collaborative robot rotation axes; Internal support for harmonic/RV reducers; Precision CNC turntables and indexing tables; Semiconductor wafer handling robots; Joints of high-end medical surgical robots; Precision rotation mechanisms in automated assembly lines; Aerospace precision testing platforms.

Precision Quality Assurance

NMT Precision Cross Roller Bearings use high-purity vacuum-degassed bearing steel as core raw materials, subject to strict incoming material and purity inspections. After precision turning, rings undergo special heat treatment and nano-level super-finishing, with strict control over raceway surface roughness, roundness, and span dimensions. Precision rollers are fully automatically sorted for size and weight to ensure consistent contact stress within the same bearing set. Cages and seals are simultaneously inspected to eliminate raw material defects. All components are assembled in a dust-free workshop. Finished products undergo rotational torque, preload, backlash, and precision dimensional verification. Unqualified products are completely rejected, ensuring the ultimate performance of batch products under high-rigidity and high-precision conditions, providing reliable precision joint support solutions for the robotics industry.

Product Series

Inner-ring split cross roller bearings (RB series), outer-ring split cross roller bearings (RE series), inner/outer-ring integrated ultra-thin cross roller bearings (RU series), cross roller bearings with mounting hole flanges (XRU series); Selection is based on installation space, rigidity requirements, rotating component types, and assembly convenience.

Brand Strength

NMT is deeply engaged in the R&D and manufacturing of precision cross roller bearings for robots. Targeting industry pain points in industrial, collaborative, and humanoid robot joints—where space is extremely limited, composite loads are complex, and precision requirements are exceptionally high—NMT continuously optimizes cross roller geometric design, nano-level finishing processes, and preload control technologies. This effectively solves fatal defects of traditional bearings such as insufficient rigidity, easy deformation, and precision degradation. It significantly enhances the dynamic response and repeatability positioning accuracy of robot joints, extends the service life of core components under high-frequency and heavy-load conditions, and helps robot manufacturing enterprises break through lightweight and high-precision design bottlenecks to seize the global high-end intelligent manufacturing market.