CRBT Series
Super-Slim Crossed Roller Bearings
10–50mm Bore | 5.5mm Cross-Section | P5/P4/P2 Grade | Ultra-Compact Design
The CRBT series is the world's thinnest crossed roller bearing type, with a cross-section height as low as 5.5mm — achieving a 69% height reduction and 38% weight reduction compared to conventional CRBS series bearings. Designed for applications where every millimeter and gram counts: compact hand robots, surveillance camera pan-tilt units, humanoid robot joints, and exoskeleton mechanisms.
Ultra-Thin Crossed Roller Bearings for Space-Constrained Precision Applications
Luoyang Songju CRBT series super-slim crossed roller bearings are manufactured to the highest precision standards in our ISO 9001:2015 certified facility in Luoyang, China. With a cross-section height of just 5.5mm, the CRBT series achieves dramatic space and weight savings — enabling designers to reduce overall mechanism size or increase shaft diameter within an existing housing envelope.
The CRBT series employs the same perpendicular (90°) cylindrical roller arrangement in V-groove raceways as larger crossed roller bearings, with anti-skewing spacer retainers between each roller. This ensures smooth, stable rotational torque and consistent running accuracy despite the ultra-thin profile. The separable outer ring design (two-piece outer ring, one-piece inner ring) facilitates easy installation and clearance adjustment.
Standard models are available in P5 (ABEC-5), P4 (ABEC-7), and P2 (ABEC-9) precision grades from GCr15 high-carbon chromium bearing steel. Open type (standard) and sealed type (suffix UU) configurations are available. Custom bore sizes, preload values, and specialty materials are available upon request for OEM applications.
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CRBT Series — Super-Slim Crossed Roller Bearing Model Parameters
Complete standard model list for CRBT super-slim crossed roller bearings. All models feature a 5mm cross-section height. Available with separators (standard) or as full complement (suffix V) for higher load capacity.
| Bearing Model | d (mm) | D (mm) | B (mm) | Cr (kN) | C0r (kN) | Mass (kg) |
|---|---|---|---|---|---|---|
| CRBT 105 A | 10 | 31 | 5 | 1.62 | 0.93 | 0.012 |
| CRBT 205 A | 20 | 31 | 5 | 1.96 | 1.63 | 0.018 |
| CRBT 305 A | 30 | 41 | 5 | 2.45 | 2.52 | 0.024 |
| CRBT 405 A | 40 | 51 | 5 | 2.84 | 3.43 | 0.031 |
| CRBT 505 A | 50 | 61 | 5 | 3.23 | 4.41 | 0.038 |
| CRBT 105 AC1 | 10 | 31 | 5 | 1.62 | 0.93 | 0.012 |
| CRBT 205 AC1 | 20 | 31 | 5 | 1.96 | 1.63 | 0.018 |
| CRBT 305 AC1 | 30 | 41 | 5 | 2.45 | 2.52 | 0.024 |
| CRBT 405 AC1 | 40 | 51 | 5 | 2.84 | 3.43 | 0.031 |
| CRBT 505 AC1 | 50 | 61 | 5 | 3.23 | 4.41 | 0.038 |
| CRBT 105 A UU | 10 | 31 | 5 | 1.62 | 0.93 | 0.012 |
| CRBT 205 A UU | 20 | 31 | 5 | 1.96 | 1.63 | 0.018 |
| CRBT 305 A UU | 30 | 41 | 5 | 2.45 | 2.52 | 0.024 |
| CRBT 405 A UU | 40 | 51 | 5 | 2.84 | 3.43 | 0.031 |
| CRBT 505 A UU | 50 | 61 | 5 | 3.23 | 4.41 | 0.038 |
All models available in P5, P4, and P2 precision grades. Standard: GCr15 bearing steel with POM separators. Suffix A = standard caged type. Suffix C1 = specified internal clearance. Suffix UU = double sealed. Suffix V = full complement type. Custom configurations available — contact our engineering team.
Why Choose Luoyang Songju CRBT Super-Slim Crossed Roller Bearings
The world's thinnest crossed roller bearing — engineered for space-constrained precision motion
Ultra-Thin — 5.5mm Cross-Section
At just 5.5mm cross-section height, the CRBT series is the world's thinnest crossed roller bearing. Achieves 69% height reduction and 38% weight reduction compared to CRBS series — enabling ultra-compact mechanism designs previously impossible with conventional bearings.
Space-Optimized Design
The 5mm width and ultra-thin cross-section allow larger shaft diameters within a given housing envelope, directly increasing mechanism rigidity. Ideal for humanoid robot joints, compact surveillance PTZ cameras, and exoskeleton pivot points.
Premium GCr15 Bearing Steel
Rings manufactured from vacuum-degassed GCr15 (100Cr6 / 52100) high-carbon chromium bearing steel. Through-hardened to 58–64 HRC for consistent hardness, wear resistance, and long-term dimensional stability in precision motion applications.
Separator vs Full Complement Options
Standard type (suffix A) features POM plastic separators for smooth low-friction rotation. Full complement type (suffix V) eliminates separators for maximum load capacity in low-speed, high-load applications. Both types support combined radial, axial, and moment loads.
Open & Sealed Configurations
Open type (standard) for greased applications with external sealing. Sealed type (suffix UU) with synthetic rubber seals on both sides for contamination protection — ideal for dusty industrial environments or where relubrication access is limited.
IKO Interchangeable
Designed as direct dimensional replacements for IKO CRBT series super-slim crossed roller bearings. Drop-in compatible with major OEM robot joint and compact mechanism designs. Custom mounting hole patterns available on request (CRBTF equivalent).
Industries & Applications for CRBT Super-Slim Crossed Roller Bearings
CRBT Series crossed roller bearings are trusted across a wide range of precision industries worldwide.
Humanoid & Compact Robots
Ultra-thin 5.5mm profile enables compact joint designs for humanoid robots, desktop robotic arms, and end-effectors where space constraints are extreme. CRBT series is the industry standard for miniature robot joint bearings.
Surveillance & PTZ Cameras
Smooth, precise pan-tilt motion in the most compact form factor available. CRBT bearings enable smaller, lighter surveillance camera gimbals with excellent pointing accuracy and minimal power consumption from low-friction separator design.
Exoskeleton Joints
38% weight savings vs conventional crossed roller bearings directly reduces the metabolic cost to exoskeleton users. Ultra-thin profile integrates seamlessly into wearable robotic systems where bulk and weight are critical design constraints.
Medical & Laboratory Devices
Compact precision rotary stages in diagnostic equipment, surgical robots, and laboratory automation. The CRBT's minimal cross-section enables instrument miniaturization without compromising positioning accuracy.
Need CRBT Super-Slim Crossed Roller Bearings?
Tell us your bore size, precision grade (P5/P4/P2), seal preference (open/UU), and quantity. Our application engineers will respond with a competitive quotation within 24 hours.