Cross Roller Bearings (RB / CRBH)

Description

1. Product Overview

Cross Roller Bearings (RB / CRBH series) are high-precision rotational components engineered with cylindrical rollers arranged perpendicularly to one another in a single compact raceway. Primarily used in robotics, machine tools, and medical imaging equipment, these bearings deliver exceptional rigidity, rotational accuracy, and moment load capacity in space-constrained assemblies. Their strategic value lies in enabling zero-backlash, high-speed operation for Industry 4.0 automation and precision manufacturing—directly reducing downtime and improving end-product tolerances for global OEMs.

2. Key Specifications & Technical Characteristics

• Material Composition: High-carbon chromium bearing steel (GCR15 / 100Cr6) with through-hardened rings; optional stainless steel (SUS440C) for corrosive environments

• Purity / Grade: ISO P5 (ABEC 5) standard; P4 (ABEC 7) available upon request; no internal voids or inclusions above 0.02mm

• Physical Characteristics:

  • Form: Inner ring, outer ring, cylindrical rollers + polyamide or brass cage

  • Bore diameter range: RB: 25mm – 2000mm / CRBH: 50mm – 500mm

  • Cross-sectional height: Extremely thin (typically 5mm – 25mm)

  • Radial runout: ≤ 5μm (P5 grade)

• Packaging Options: VCI anti-corrosion paper + individual polybag + foam-lined carton; bulk wooden crates for large-diameter units

• Shelf Life: 5 years when stored in dry (≤65% RH), non-corrosive, vibration-free environment with original packaging unopened

3. Core Industrial Applications

• Industrial Robotics (Collaborative & SCARA): Used in robot wrists, swivel joints, and base rotation units – outperforms crossed-roller alternatives with 40% higher moment rigidity at same cross-section, enabling higher payloads and faster cycle times.

• Machine Tools (Rotary Tables & Indexing Drives): Delivers zero backlash and consistent preload under heavy cutting loads – reduces positional deviation by 30% compared to angular contact ball bearings, directly improving part surface finish.

• Medical Equipment (CT Scanners & Surgical Robots): Smooth, low-friction rotation with minimal vibration – critical for image clarity and haptic precision; CRBH’s sealed variant eliminates lubricant contamination risk.

• Semiconductor Manufacturing (Wafer Handling Robots): Cleanroom-compatible, low particle generation – maintains class 1 cleanroom compliance while sustaining 5,000+ hours of continuous indexing.

Why superior: The RB/CRBH design eliminates the need for separate raceways for radial and axial loads, slashing assembly height and weight while doubling service life under combined loads versus needle roller or ball bearing configurations.

4. Competitive Advantages

• Quality Consistency: 100% dimensional inspection (CMM + laser interferometer) and 100% torque testing per batch; statistically controlled heat treatment with hardness uniformity within ±1 HRC.

• Supply Reliability: Buffer stock of top 20 sizes (RB 80 to RB 400) available for 48-hour dispatch; lead times 4–6 weeks for non-standard sizes (industry average: 8–12 weeks).

• Logistics Capability: Dual sourcing from ISO 9001:2022 and IATF 16949 certified facilities; export packaging certified for sea freight shock/vibration.

• Price Competitiveness: 15–20% lower total landed cost than EU/JP Tier 1 brands while meeting identical DIN/ISO tolerances.

• Sustainability: Chrome-free passivation on request; 98% steel recyclability; grease options with high biodegradability (OECD 301B compliant).

• Technical Support: Full 3D CAD models (STEP/IGES) + mounting torque guidelines + FEA load-life reports provided pre-purchase.

5. Commercial & Supply Information

• Minimum Order Quantity (MOQ):

  • Standard sizes (RB / CRBH 80–400): 10 units

  • Large diameters (RB >500mm): 2 units

  • Custom (non-catalog bore/OD): 20 units

• BULK 20MT Loading Capacity (20-foot container):

  • Small bearings (≤150mm OD): approx. 4,500–6,000 units (depending on cross-section)

  • Medium bearings (151–300mm OD): approx. 1,200–1,800 units

  • Large bearings (301–500mm OD): approx. 400–600 units

  • Extra large (500mm+ OD): consult logistics; typically shipped individually on pallets via flat rack or OOG container