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What is the RU-Type Crossed Roller Bearing?

The RU-type crossed roller bearing (also called RU cross roller bearing) is a split inner ring design that allows for easy installation and high precision in applications requiring compactness, rigidity, and multi-directional load capacity.Unlike the RA-type (which has a one-piece inner ring), the RU-type features a two-part inner ring with mounting holes, making it ideal for applications where space constraints or complex assembly processes are a concern. 

NewBee Transmission's RU cross roller bearings are engineered for high rotational accuracy (P4/P2 grade) and can handle radial, axial, and moment loads simultaneously, making them essential for robotics, automation, and precision machinery.

Features of the RU-Type Crossed Roller Bearing

1.Split Inner Ring Design  

The two-piece inner ring simplifies installation and maintenance, especially in confined spaces. 

Mounting holes on the inner ring allow for direct bolting to machinery, reducing alignment errors.

2.High Load Capacity & Rigidity  

90° crossed roller arrangement distributes loads evenly, supporting radial, axial, and tilting moments in a single bearing. 

High rigidity due to large contact area between rollers and raceways, minimizing deformation under heavy loads.

3.Ultra-Precise Rotation (P4/P2 Grade)  

Radial runout ≤ 0.002mm, ensuring smooth and accurate motion for high-precision applications. 

Ideal for CNC rotary tables, robotic arms, and optical equipment where minimal vibration is critical.

4.Space-Saving & Lightweight  

Thin-section design reduces machine footprint while maintaining high load capacity. 

Available in inner diameters from 50mm to 200mm, with customizable sizes upon request.

 5.Long Service Life  

Made from high-carbon chromium steel (GCr15) or stainless steel (440C) for durability. 

Optional ceramic rollers for extended life in high-speed or corrosive environments. 

Applications of RU-Type Crossed Roller Bearings  

Due to their high precision, compact design, and ease of installation, RU cross roller bearings are widely used in:  

Industrial Robots: Rotary joints, robotic arm linkages, and harmonic drive supports. 

Machine Tools: CNC rotary tables, indexing heads, and multi-axis machining centers. 

Medical Equipment: CT/MRI scanner gantries, surgical robot rotation mechanisms. 

Semiconductor Manufacturing: Wafer handling robots, precision alignment stages. 

Optical & Measuring Instruments: Telescope mounts, laser cutting rotary platforms.

Factors Affecting RU-Type Bearing Price  

1.Material  Standard GCr15 steel:

Cost-effective for general industrial use. 

440C stainless steel: 20-30% more expensive, ideal for corrosive or medical environments. 

Ceramic rollers: Higher cost but offer superior performance in extreme conditions. 

2.Precision Grade  

P4(standard): Suitable for most industrial applications. 

P2(ultra-precision):15-25% more expensive, used in semiconductor/medical fields. 

3.Size & Customization  

Larger bearings (>150mm inner diameter) cost more due to material and machining complexity. 

Special lubricants, seals, or preload adjustments increase price by10-20%. 

How to Choose the Right RU Cross Roller Bearing?  

1.Check Dimensions – Match inner diameter (d), outer diameter (D), and width (B) to your application. 

2.Determine Load Requirements – Ensure the bearing can handle combined radial, axial, and moment loads. 

3.Precision Needs – Select P4 for general use or P2 for ultra-high precision. 

4.Environmental Conditions – Choose stainless steel (440C) for humid/cleanroom environments. 

5.Supplier Reliability – Opt for certified manufacturers like NewBee Transmission for quality assurance.

Why Choose NewBee Transmission for RU Cross Roller Bearings?  

Factory-direct pricing with no middleman markup. 

Custom solutions available (special sizes, materials, lubrication). 

ISO 9001-certified production with strict quality control. 

Technical support for bearing selection and integration. 

For quotes, specifications, or customization, contact:  

frank@newbeetrans.com  

www.newbeetrans.com