As precision equipment continues to advance toward higher accuracy, higher rigidity, and more compact designs, bearings are required to simultaneously withstand multi-directional loads including radial, axial, and tilting moments within limited installation space. Traditional multi-bearing combination solutions often consume significant axial space, limiting equipment miniaturisation and lightweight design. Crossed roller bearings, with their unique structural design—cylindrical rollers arranged at 90° perpendicularly to each other in V-shaped raceways—enable a single bearing to simultaneously withstand radial loads, axial loads, and moment loads in multiple directions. They have gained widespread application in industrial robot joints, precision turntables, CNC machine tools, medical equipment, and other fields.

 

NMT Crossed Roller Bearings, with line-contact high rigidity and ultra-thin compact design as core characteristics, provide ultimate support for precision rotation and robot joints. By strictly controlling roller crowning profiles and raceway surface integrity, NMT effectively reduces stress peaks in the rolling contact area—even after millions of alternating load cycles, the bearing's rotational accuracy remains stable and clearances do not gradually increase.

 

High rigidity is the most prominent characteristic of NMT crossed roller bearings. Cylindrical rollers carry loads through line contact, with contact rigidity far superior to point-contact ball bearings. Compared to conventional bearings, the rigidity of crossed roller bearings can be increased by 3 to 4 times. When subjected to tilting moments, a single crossed roller bearing is equivalent to the combined effect of multiple ordinary bearings. This characteristic makes it an ideal choice for applications with stringent rigidity requirements such as industrial robot joints and precision turntables.

 

Ultra-thin compact design is another core advantage of NMT crossed roller bearings. Rollers are arranged at 90° crossings within the same space, enabling the bearing to achieve high-rigidity load carrying with extremely small cross-section height. NMT has unique processes for handling rolling consistency in crossed roller bearings—flexible pocket structures keep rollers stable during high-speed operation or frequent motion direction changes, effectively controlling torque fluctuations.

 

High rotational accuracy is the fundamental quality of NMT crossed roller bearings. Separators or cages between rollers effectively prevent roller tilting and mutual friction, avoiding abnormal increases in rotational torque. Split inner and outer ring structures allow precise adjustment of bearing clearances, enabling high-accuracy rotational motion even when preload is applied. NMT crossed roller bearings are available in P5, P4, and even P2 precision grades, meeting diverse requirements from general precision equipment to high-end applications.

 

NMT also offers integrated designs that transfer positioning functions from the housing to the bearing itself—integrating high-hardness locating tapers on inner and outer rings. Through precision grinding, these tapers form self-centring rigid connections with matching taper holes on robot interfaces. Even after thousands of quick-change cycles, there is absolutely no need for incremental compensation of tightening torque. This innovative design significantly simplifies equipment structure and enhances overall system rigidity.

 

Space savings represent significant value of NMT crossed roller bearings. Inner and outer ring dimensions are minimised to the extreme, with ultra-thin structures approaching the limits of miniaturisation. One NMT crossed roller bearing can replace multiple bearing combinations, and the axial space saved can be allocated to cables, air tubes, or even force sensors, enabling robot bodies to maintain high rigidity while possessing more powerful end-integration capabilities.

 

Core Product Advantages

Rollers arranged at 90° crossings in V-shaped raceways, a single bearing simultaneously withstanding radial, axial, and tilting moment loads in multiple directions;

 

Line-contact structure achieving high-rigidity load carrying, with rigidity improved by 3 to 4 times over conventional bearings;

 

NMT flexible pocket cage design keeping rollers stable at high speeds or during frequent direction changes, with torque fluctuations effectively controlled;

 

Split inner and outer ring structures allowing precise clearance adjustment, enabling high-accuracy rotational motion even under preload;

 

Ultra-thin compact design with minimised inner and outer ring dimensions, significantly saving installation space;

 

Stress peak control technology—strict control of roller crowning profiles and raceway surface integrity, maintaining stable accuracy under alternating loads;

 

Integrated locating taper design (optional) with self-centring rigid connection, eliminating incremental tightening torque compensation;

 

Precision grades covering P5, P4, and P2, adapting to equipment with different accuracy requirements.

 

Typical Applications

Industrial robots—precision rotational support for shoulder, waist, wrist, elbow, and finger joints; CNC machine tools—precise positioning for rotary tables, indexing plates, and vertical grinders; Medical equipment—precision rotation mechanisms for CT scanner slip ring systems and surgical robots; Semiconductor equipment—high-reliability rotation for wafer transfer devices in clean environments; Precision test turntables and optical telescopes—high-accuracy angular positioning and stable tracking; Large radar antennas—stable slewing for long-term continuous outdoor operation; Automated production lines—high-rigidity support for rotary platforms and sorting devices.

 

Quality Assurance

NMT crossed roller bearing quality assurance covers the entire process from raw materials to finished products. High-purity alloy steel undergoes spectral analysis, inclusion rating, and grain size testing upon incoming inspection. Precision forging and gradient heat treatment ensure uniform raceway surface hardness and good core toughness. Raceways undergo precision grinding and superfinishing with stable surface quality control. Cylindrical rollers undergo multi-stage grinding and precision grading with precise crowning profile control and good dimensional consistency.

 

Cages are one of the core components of crossed roller bearings. NMT employs flexible pocket structures to ensure stable roller motion under various operating conditions. Assembly takes place in clean environments with precise clearance and preload control. Finished products pass torque, vibration, rotational accuracy, and run-in tests, with complete data archived. Rust-preventive packaging ensures flawless delivery.

 

Product Range

RB type—outer ring split, inner ring integrated design, suitable for applications with high inner ring rotational accuracy requirements; RE type—inner ring split, outer ring integrated design, suitable for applications with high outer ring rotational accuracy requirements; RU type—integrated inner and outer rings with pre-machined mounting holes, eliminating need for fixing flanges and support housings; RA type—outer ring split, ultra-thin structure for maximum space savings; P5, P4, and P2 precision grades available; Open and sealed configurations available; Custom integrated locating taper designs available upon request.

 

Brand Strength

NMT has been dedicated to the research, development, and manufacturing of precision bearings for over a decade. As a high-precision, high-rigidity category within the NMT product portfolio, crossed roller bearings serve high-end equipment sectors including industrial robots, CNC machine tools, medical equipment, semiconductor equipment, radar communications, and other fields with line-contact high rigidity, ultra-thin compact design, and high rotational accuracy. The company operates complete precision machining production lines, professional testing laboratories, and an experienced technical team.

 

NMT crossed roller bearings deeply integrate the advantages of the unique crossed roller structure with precision manufacturing processes—from precise control of roller crowning profiles to flexible pocket cage design, from superfinished raceway processing to integrated positioning solutions—continuously optimising across the three dimensions of high rigidity, compactness, and rotational accuracy. Bearings are the core of precision rotation systems. With professional capability and quality commitment, NMT provides trustworthy crossed roller bearing products for high-end equipment.