Precision Crossed
Roller Bearings
CRBT / CRBH / RA / RB / RE / RU Series | 20–500mm Bore | P5/P4/P2 Grade | Multi-Directional Load
Cylindrical rollers arranged perpendicularly at 90° in V-groove raceways — a single bearing handles radial, axial, and moment loads simultaneously. 3–4× higher rigidity than equivalent double-row angular contact ball bearings. Trusted across robotics, machine tool rotary tables, medical imaging equipment, and precision indexing mechanisms.
Precision Crossed Roller Bearings for Robotics & Precision Rotary Equipment
Luoyang Songju precision crossed roller bearings are manufactured in six dimensional series — CRBT, CRBH, RA, RB, RE, and RU — engineered for applications requiring compact design, high rigidity, and multi-directional load handling in a single bearing assembly. Each bearing is manufactured from high-carbon chromium bearing steel GCr15 (100Cr6 / 52100) in our ISO 9001:2015 certified facility.
The defining feature of crossed roller bearings is the perpendicular (90°) arrangement of cylindrical rollers in V-groove raceways, separated by anti-skewing spacer retainers. This configuration enables a single bearing to simultaneously support radial loads, axial loads in both directions, and tilting moment loads — eliminating the need for paired bearing arrangements and simplifying adjacent structure design.
Available in P5 (ABEC-5), P4 (ABEC-7), and P2 (ABEC-9) precision grades with adjustable clearance or preload. Standard models ship with a light preload optimized for general industrial applications; custom preload values are available upon request for ultra-precision motion control applications.
Crossed Roller vs. Ball Bearings
3–4× Higher Rigidity
Line contact between cylindrical rollers and raceways provides significantly greater stiffness than point contact in ball bearings — critical for precision positioning and heavy cutting applications.
Multi-Directional Load in One Bearing
Radial + axial (both directions) + moment loads handled simultaneously. Replaces complex multi-bearing arrangements, saving space, weight, and assembly cost.
Adjustable Clearance & Preload
Separable inner and outer ring design allows fine adjustment of bearing clearance or application of preload to achieve zero-clearance or negative-clearance operation for maximum precision.
Six Series for Every Application
From super-slim CRBT to integrated-mount RU — select the right crossed roller bearing for your design requirements
CRBT Series
World's thinnest crossed roller bearing — cross-section height as low as 5.5mm. Ideal for compact hand robots, surveillance cameras, and space-constrained precision mechanisms.
CRBH Series
Integrated inner and outer ring design — thin section, no mounting holes required. The most versatile series for robot joints, machine tool rotary axes, and medical positioning equipment.
RA / RAU Series
Thin-walled, lightweight design specifically engineered for collaborative robots, CNC direct-drive (DD) motors, CT scanners, and surgical robots where every gram and millimeter counts.
RB Series
Separable outer ring design for inner ring rotation applications. The standard cross-roller type for index tables, rotary positioning tables, and machine tool turntables.
RE Series
Two-piece inner ring design for outer ring rotation applications. Same mounting dimensions as RB series but optimized for applications where the outer ring is the rotating element.
RU Series
Integrated inner and outer ring with pre-drilled mounting holes — no flange or housing needed. Ideal for harmonic reducers and both inner & outer ring rotation applications.
Why Choose Luoyang Songju Crossed Roller Bearings
Engineered for precision positioning, multi-directional loads, and maximum rigidity in compact design envelopes
Multi-Directional Load Handling
Cylindrical rollers arranged at 90° in V-groove raceways simultaneously support radial, axial (both directions), and moment loads. One bearing replaces complex multi-bearing arrangements — reducing system complexity and assembly cost.
3–4× Higher Rigidity
Line contact between cylindrical rollers and raceways provides significantly greater stiffness than point-contact ball bearings. Typically 3–4 times more rigid than equivalently sized double-row angular contact ball bearings.
Premium GCr15 Bearing Steel
Rings manufactured from vacuum-degassed GCr15 (100Cr6 / 52100) high-carbon chromium bearing steel. Through-hardened to 58–64 HRC with controlled retained austenite content for long-term dimensional stability under varying loads and temperatures.
Adjustable Clearance & Preload
Separable inner and outer ring construction enables fine adjustment of internal clearance. Apply negative clearance (preload) for zero-backlash operation in ultra-precision positioning systems. Standard preload classes: Light, Medium, and Heavy.
Anti-Skewing Spacer Retainers
Precision spacer retainers between each roller prevent skewing and maintain correct roller alignment throughout the rotation cycle. Results in stable rotational torque, reduced friction variation, and consistent running accuracy.
Easy Handling & Installation
Rings, rollers, and spacer retainers are secured together as a single assembly — preventing separation during handling and installation. Integrated mounting holes on RU series eliminate the need for additional flanges or housings.
Crossed Roller Bearing Model Parameters
Standard model list covering CRBT, CRBH, RA, RB, RE, and RU series. All models available in P5, P4, and P2 precision grades. Custom bore sizes and configurations available upon request.
| Bearing Model | Series | d (mm) | D (mm) | B (mm) | Cr (kN) | C0r (kN) | Mass (kg) |
|---|---|---|---|---|---|---|---|
| CRBT 105 A | CRBT | 10 | 31 | 5 | 1.62 | 0.93 | 0.01 |
| CRBT 205 A | CRBT | 20 | 31 | 5 | 1.96 | 1.63 | 0.02 |
| CRBT 305 A | CRBT | 30 | 41 | 5 | 2.45 | 2.52 | 0.02 |
| CRBT 405 A | CRBT | 40 | 51 | 5 | 2.84 | 3.43 | 0.03 |
| CRBT 505 A | CRBT | 50 | 61 | 5 | 3.23 | 4.41 | 0.04 |
| CRBH 3010 A | CRBH | 30 | 55 | 10 | 7.60 | 8.37 | 0.12 |
| CRBH 4010 A | CRBH | 40 | 65 | 10 | 8.61 | 10.60 | 0.16 |
| CRBH 5013 A | CRBH | 50 | 80 | 13 | 17.30 | 20.90 | 0.29 |
| CRBH 6013 A | CRBH | 60 | 90 | 13 | 18.80 | 24.30 | 0.33 |
| CRBH 7013 A | CRBH | 70 | 100 | 13 | 20.10 | 27.70 | 0.38 |
| CRBH 8016 A | CRBH | 80 | 120 | 16 | 32.10 | 43.40 | 0.74 |
| CRBH 10020 A | CRBH | 100 | 150 | 20 | 50.90 | 72.20 | 1.45 |
| CRBH 12025 A | CRBH | 120 | 180 | 25 | 73.40 | 108.00 | 2.62 |
| RA 5008 | RA | 50 | 66 | 8 | 5.10 | 7.19 | 0.08 |
| RA 6008 | RA | 60 | 76 | 8 | 5.68 | 8.68 | 0.09 |
| RA 7008 | RA | 70 | 86 | 8 | 5.98 | 9.80 | 0.10 |
| RA 8008 | RA | 80 | 96 | 8 | 6.37 | 11.30 | 0.11 |
| RA 10008 | RA | 100 | 116 | 8 | 7.15 | 13.90 | 0.15 |
| RA 12008 | RA | 120 | 136 | 8 | 7.84 | 16.50 | 0.18 |
| RA 16013 | RA | 160 | 186 | 13 | 23.30 | 44.90 | 0.62 |
| RA 20013 | RA | 200 | 226 | 13 | 25.80 | 54.70 | 0.78 |
| RB 3010 | RB | 30 | 55 | 10 | 7.35 | 8.36 | 0.12 |
| RB 4010 | RB | 40 | 65 | 10 | 8.33 | 10.60 | 0.15 |
| RB 5013 | RB | 50 | 80 | 13 | 16.70 | 20.90 | 0.29 |
| RB 6013 | RB | 60 | 90 | 13 | 18.00 | 24.30 | 0.33 |
| RB 8016 | RB | 80 | 120 | 16 | 30.10 | 42.10 | 0.74 |
| RB 10020 | RB | 100 | 150 | 20 | 33.10 | 50.90 | 1.45 |
| RB 12025 | RB | 120 | 180 | 25 | 66.90 | 100.00 | 2.62 |
| RB 20030 | RB | 200 | 280 | 30 | 114.00 | 200.00 | 6.70 |
| RB 30035 | RB | 300 | 395 | 35 | 183.00 | 367.00 | 13.40 |
| RB 50040 | RB | 500 | 600 | 40 | 239.00 | 607.00 | 26.00 |
| RE 3010 | RE | 30 | 55 | 10 | 7.35 | 8.36 | 0.12 |
| RE 4010 | RE | 40 | 65 | 10 | 8.33 | 10.60 | 0.16 |
| RE 5013 | RE | 50 | 80 | 13 | 16.70 | 20.90 | 0.27 |
| RE 8016 | RE | 80 | 120 | 16 | 30.10 | 42.10 | 0.70 |
| RE 10020 | RE | 100 | 150 | 20 | 33.10 | 50.90 | 1.45 |
| RE 12025 | RE | 120 | 180 | 25 | 66.90 | 100.00 | 2.62 |
| RE 20030 | RE | 200 | 280 | 30 | 114.00 | 200.00 | 6.70 |
| RE 30035 | RE | 300 | 395 | 35 | 183.00 | 367.00 | 13.40 |
| RE 50040 | RE | 500 | 600 | 40 | 239.00 | 607.00 | 26.00 |
| RU 42 (CRBF 108) | RU | 10 | 52 | 8 | 2.91 | 2.43 | 0.12 |
| RU 66 (CRBF 2012) | RU | 20 | 70 | 12 | 7.60 | 8.37 | 0.31 |
| RU 85 (CRBF 2512) | RU | 25 | 80 | 12 | 8.61 | 10.60 | 0.40 |
| RU 124 (CRBF 3515) | RU | 35 | 95 | 15 | 17.30 | 20.90 | 0.66 |
| RU 148 (CRBF 5515) | RU | 55 | 120 | 15 | 20.10 | 27.70 | 0.96 |
| RU 178 (CRBF 8022) | RU | 80 | 165 | 22 | 51.10 | 72.00 | 2.63 |
| RU 228 (CRBF 9025) | RU | 90 | 210 | 25 | 52.40 | 77.40 | 3.50 |
| RU 297 (CRBF 11528) | RU | 115 | 240 | 28 | 73.40 | 108.00 | 4.80 |
All models available in P5, P4, and P2 precision grades. Standard material: GCr15 (100Cr6/52100) bearing steel. CRBT: standard caged (A) type, full complement (V) on request. CRBH/RU: POM separators. RB/RE: full complement. UU suffix = double sealed. Data per IKO/THK published catalogs — contact engineering for complete model range and custom configurations.
Industries & Applications for Crossed Roller Bearings
Precision crossed roller bearings deliver measurable performance advantages across a wide range of demanding industries
Industrial Robotics
Robot swivel joints, collaborative robot (cobot) arms, harmonic drive reducers, and end-of-arm tooling. CRBT and RA series are the preferred choice for compact, lightweight robotic applications.
Machine Tools
CNC rotary tables, index tables, tool changers, and trunnion tables. RB and RE series are the standard choice — providing the high rigidity and precision required for heavy cutting operations.
Medical Equipment
CT scanner gantries, surgical robots, MRI patient tables, and radiation therapy positioning systems. RA and RU series with ultra-smooth, low-noise rotation are specified for medical imaging applications.
Aerospace & Defense
Satellite positioning mechanisms, antenna pedestals, radar turntables, and optical tracking mounts. Custom configurations available with specialty materials and lubrication for extreme environments.
Semiconductor Manufacturing
Wafer handling robots, inspection stages, and precision alignment systems. Ultra-precision P2 grade bearings with clean-room-compatible lubrication ensure contamination-free operation.
Wind Turbines
Pitch and yaw control bearings. Specialized sealed designs with corrosion-resistant coatings for long service life in harsh outdoor environments with minimal maintenance requirements.
Precision Optics & Surveillance
Camera pan-tilt units, telescope mounts, laser scanning platforms, and optical inspection systems. CRBT ultra-slim bearings enable compact, lightweight designs with smooth, precise motion.
Crossed Roller Bearing Installation Steps
Proper installation ensures optimal bearing performance, precision, and extended service life
Clean & Inspect
Thoroughly clean the bearing mounting surfaces, shaft, and housing with lint-free cloths and high-purity solvent. Inspect all mating surfaces for burrs, nicks, or contamination. Verify mounting dimensions against specification.
Verify Runout & Fit
Measure shaft and housing bore runout using a dial indicator. Confirm recommended fit tolerances: typically a slight interference on the rotating ring and a clearance or transition fit on the stationary ring. Parallelism and flatness of mounting faces must be within specification.
Mount the Bearing
For CRBH/RB/RE series: press the ring with the tighter fit first using a mounting tool that applies even force around the circumference. For RU series: bolt directly to the mounting surface using the integrated mounting holes. Never apply mounting force through the rolling elements.
Preload & Verify
Adjust preload per specification using shims or threaded retainers. After installation, rotate the bearing by hand — verify smooth, consistent torque without binding. Measure axial and radial runout. Run at low speed initially and monitor for abnormal noise, vibration, or temperature rise.
Need Precision Crossed Roller Bearings?
Tell us your requirements — bore size, series (CRBT/CRBH/RA/RB/RE/RU), precision grade (P5/P4/P2), mounting configuration, and quantity. Our application engineers will respond with a competitive quotation and detailed technical documentation within 24 hours.