The RB12025 cross roller bearing has a 120 mm bore, 180 mm outside diameter and 25 mm width. Its crossed cylindrical roller arrangement supports radial loads, axial loads in both directions and overturning moments within one compact bearing assembly.
With a basic dynamic radial load rating of 66.9 kN and a basic static radial load rating of 100 kN, RB12025 provides substantially higher load capacity than narrower 120 mm bore models. Its integrated inner ring and split outer ring make it suitable for robot positioners, CNC rotary tables, indexing mechanisms and precision automation equipment.
Accuracy, clearance, preload, sealing and lubrication configurations can be confirmed according to the operating conditions and approved mounting drawing.
RB12025 Cross Roller Bearing Overview
The RB12025 cross roller bearing is a high-rigidity precision bearing with a 120 mm bore, 180 mm outside diameter and 25 mm width. It is designed for rotary mechanisms that require a large through-bore, high combined-load capacity and resistance to overturning moments.
Its cylindrical rollers are arranged alternately at 90 degrees between the inner and outer raceways. This crossed arrangement enables one bearing to support radial loads, axial loads in both directions and moment loads.
RB12025 uses an integrated inner ring and a split outer ring. This structure is commonly selected for applications requiring accurate inner-ring rotation, high rigidity and compact axial installation.
Explore other sizes in our RB Series Cross Roller Bearings range.
GCr15, GCr15SiMn or 100Cr6, subject to specification
*Mounting dimensions are catalogue references. Final shaft, housing, flange and chamfer dimensions must follow the approved LYDL drawing supplied with the quotation or order.
The basic load ratings are reference values for bearing selection and life calculations. They are not maximum permissible application loads. Radial, axial and moment loads must be evaluated as a combined equivalent load with appropriate life and static safety factors.
Structure and Load Capability
Adjacent cylindrical rollers inside the RB12025 are arranged with their axes crossing at right angles. The rollers make line contact with the raceways, providing high rigidity and limited elastic deformation under load.
This internal geometry enables the bearing to carry:
Radial loads
Axial loads in both directions
Overturning moment loads
Combined radial, axial and moment loads
The 148.7 mm roller pitch circle helps distribute load around a relatively large diameter. Combined with the 25 mm bearing width and 30 mm radial cross-section, this makes RB12025 suitable for applications requiring greater rigidity and static capacity than narrower 120 mm bore models.
The split outer-ring retaining screws are normally intended to prevent ring separation during handling and installation. They must not be treated as structural mounting bolts unless the approved drawing states otherwise.
Key Advantages of RB12025
100 kN Basic Static Radial Rating
RB12025 provides a basic static radial load rating of 100 kN. This makes it suitable for mechanisms exposed to substantial stationary loads, indexing loads or moment loads, provided that the complete equivalent-load and static-safety calculations are satisfied.
Substantially Higher Capacity Than RB12016
RB12016 has the same 120 mm bore but a smaller 150 mm outside diameter and 16 mm width. RB12025 uses a larger bearing section and provides substantially higher dynamic and static radial ratings.
High Moment Rigidity
The crossed roller arrangement resists tilting deformation, making RB12025 suitable for rotary axes where angular displacement must be controlled.
Large 120 mm Through-Bore
The bore provides space for drive shafts, cables, pneumatic lines, hydraulic lines, optical components or other machine elements passing through the rotary axis.
Combined-Load Support
One bearing can carry radial, bidirectional axial and overturning moment loads, helping simplify the surrounding bearing arrangement.
Configurable Precision and Preload
Accuracy, clearance, preload, sealing and lubrication can be specified according to positioning requirements, operating speed, rigidity and permissible running torque.
Typical RB12025 Applications
RB12025 can be considered for:
Industrial robot base and waist axes
Robot positioners
Welding manipulators
CNC rotary tables
Machine-tool indexing tables
Precision rotary actuators
Direct-drive rotary mechanisms
Semiconductor manufacturing equipment
Optical inspection systems
Medical imaging equipment
Measuring and testing systems
Automated assembly equipment
Final selection must consider the actual radial load, axial load, overturning moment, shock load, speed, operating cycle, required life, mounting rigidity, lubrication and acceptable running torque.
RB12025 Compared with RB10016 and RB15025
The RB12025 cross roller bearing offers a 120 mm bore and 25 mm width. The following comparison helps identify differences in installation space, radial load ratings and weight.
RB10016 has a smaller installation envelope and lower mass. RB12025 provides higher radial load ratings while requiring less space than RB15025. RB15025 offers a larger bore and higher radial load ratings when the surrounding structure can accommodate its dimensions.
These models are not direct replacements because their mounting dimensions differ. The listed C and C₀ values are basic radial catalogue ratings, not allowable limits for combined radial, axial and moment loads. Final LYDL specifications and suitability must be confirmed against the approved drawing and application requirements.
Reference: THK Model RB Dimensional Tables.
For related sizes, see the RB10016 Cross Roller Bearing and RB15025 Cross Roller Bearing.
RB12025 Common Configurations and Suffix Guide
Suffix systems vary between manufacturers. Seal, clearance, preload and accuracy codes must be interpreted according to the applicable catalogue and purchase specification.
The following RB12025 codes are enquiry examples. Final LYDL designations and numerical requirements must be confirmed in the quotation.
Both-side seals with controlled negative clearance or preload
Preload and running torque
RB12025UUC1
Both-side seals with specified C1 clearance
Manufacturer-specific limits
RB12025UUP5
Both-side seals with P5 accuracy
Controlled surfaces and inspection limits
RB12025UUP4
Both-side seals with P4 accuracy
Runout and dimensional requirements
RB12025UUCC0P4
Both-side seals, controlled preload and P4 accuracy
Complete approved specification
RB12025UUCC0P2
Both-side seals, controlled preload and P2 accuracy
Engineering review and availability
Seal Suffixes
No suffix: Generally indicates an open configuration, but the supplied condition must be confirmed.
U: Commonly indicates a seal fitted on one side. The required side should be specified.
UU: Commonly indicates seals fitted on both sides.
DD: Used by NSK for seals fitted on both sides.
E: Used by NSK for an open bearing without seals.
Clearance and Preload Suffixes
CC0: Used in the THK system for controlled negative clearance or preload.
C0: A specified clearance category. In the THK system, C0 indicates positive clearance rather than zero clearance.
C1: A manufacturer-specific positive-clearance category.
C8: Used in the NSK NRXT system for negative clearance.
T1, C1 and C2: Clearance classifications used in the IKO crossed roller bearing system.
Clearance and preload affect moment rigidity, positioning behaviour, starting torque, running torque and heat generation. A suffix without a numerical specification may be insufficient for a precision order.
Accuracy Suffixes
P6: Accuracy class 6
P5: Accuracy class 5
P4: Accuracy class 4
P2: Accuracy class 2
PE5, PE4 or PE2: THK-style codes combining rotational and dimensional accuracy requirements
Higher accuracy should only be specified when the shaft, housing, flange and assembly process can maintain the required installed accuracy.
The table demonstrates why identical boundary dimensions do not guarantee identical performance.
Before replacing another brand, compare:
Complete model number and suffixes
Inner and outer ring construction
Roller complement or separator design
Shoulder and chamfer dimensions
Dynamic and static load ratings
Clearance or preload
Accuracy class
Seal arrangement
Lubrication
Running torque
Mounting and clamping method
Cross-brand model numbers are provided for preliminary identification and engineering comparison, not as a guarantee of interchangeability.
Material, Sealing and Lubrication
Depending on the confirmed specification, bearing-steel options can include GCr15, GCr15SiMn or 100Cr6.
Open bearings require suitable lubrication and effective external sealing. Sealed configurations provide additional protection against dust ingress and grease leakage but may generate higher starting and running torque.
Lubricant selection should consider:
Rotational speed
Combined operating load
Duty cycle
Operating temperature
Required running torque
Environmental contamination
Relubrication interval
Compatibility with surrounding materials
Do not mix greases with unknown base-oil or thickener compatibility.
Inspection and Quality Control
Inspection requirements should be agreed before production. Depending on the order specification, the inspection scope may include:
Bore and outside-diameter measurement
Bearing width inspection
Dimensional and rotational runout
Radial clearance or preload verification
Starting and running torque
Rotation smoothness
Raceway and surface-condition inspection
Hardness verification
Cleanliness and appearance inspection
Laser marking verification
Final packaging inspection
Material certificates, inspection reports or additional documentation should be requested before order confirmation.
Installation Recommendations
To preserve the rigidity and accuracy of RB12025:
Clean the bearing, shaft, housing, flange and mounting surfaces.
Remove burrs and raised edges from all mating components.
Confirm shaft and housing tolerances against the approved drawing.
Verify that the housing and clamping flange have sufficient rigidity.
Apply installation force only to the ring being fitted.
Never transmit mounting force through the rollers.
Support the split outer ring during handling and installation.
Tighten flange bolts gradually in a diagonal sequence.
Apply uniform clamping force around the full circumference.
Check running torque and rotational smoothness after installation.
Protect open bearings from contamination and lubricant loss.
Measure final runout after completing the full rotary assembly.
An insufficiently rigid housing or uneven flange pressure can reduce the installed rigidity and cause abnormal running torque even when the bearing itself meets its inspection requirements.
Information Required for RB12025 Selection
Please provide:
Radial load
Axial load
Overturning moment
Shock or vibration load
Maximum and continuous speed
Operating cycle
Required service life
Required rotational accuracy
Permissible starting and running torque
Clearance or preload requirement
Shaft and housing drawing
Operating temperature
Sealing and lubrication requirements
Quantity and destination
These conditions allow the bearing, preload, lubrication and mounting arrangement to be evaluated together.
Why Source RB12025 From LYDL?
LYDL supplies precision bearings for robotics, machine tools, automation systems, measuring equipment and industrial rotary mechanisms. Luoyang Deeplink Technology Co., Ltd. integrates machining, grinding, assembly, inspection, packaging and international order support.
Available project support includes:
Standard RB-series production
Accuracy-grade selection
Clearance and preload control
Seal and grease configuration
Dimensional inspection
Rotational-accuracy inspection
Running-torque verification
Laser marking
Application-based selection support
Export packaging
OEM and customized bearing solutions
Engineering and Selection FAQ for RB12025
Why would an engineer choose RB12025 instead of RB12016?
Both models have a 120 mm bore, but RB12025 has a larger 180 mm outside diameter and 25 mm width. Its basic dynamic and static radial ratings are substantially higher. RB12016 is preferable when low mass and minimum space are priorities, while RB12025 is better suited to higher-load and higher-rigidity applications.
Does the 100 kN static rating mean RB12025 can safely carry a 100 kN working load?
No. The 100 kN value is a basic static radial load rating, not a direct permissible working load. Radial, axial and moment loads must be converted into an equivalent static load, after which an appropriate static safety factor must be applied.
How should an overturning moment be considered when selecting RB12025?
The moment load must be converted into an equivalent load using the roller pitch circle diameter and the applicable manufacturer calculation method. The resulting equivalent load should then be used for rating-life and static-safety calculations.
Does applying more preload always improve RB12025 performance?
No. Preload can increase rigidity and reduce internal movement, but excessive preload can increase running torque, heat generation and sensitivity to mounting errors. The correct preload should balance rigidity, torque, speed and service life.
What housing features are important for a 100 kN static-rating bearing?
The housing and clamping flange should have sufficient thickness and rigidity to distribute load evenly. Flat mounting surfaces, controlled fits, suitable bolt spacing and uniform flange pressure are essential. A flexible housing can limit the practical benefit of a high-rigidity bearing.
Is RB12025 suitable for a robot positioner or CNC rotary table?
It can be suitable when the calculated combined load, overturning moment, speed, accuracy and service-life requirements fall within the selected bearing specification. The complete mounting structure and drive system must also provide sufficient rigidity.
Can RB12025 directly replace CRB12025 or NRXT12025?
Not without verification. The models share nominal boundary dimensions, but their published load ratings, masses, internal structures, clearances and mounting recommendations differ. Compare the complete model number, suffixes and approved drawings before replacement.
Should RB12025 be supplied open or sealed?
A sealed bearing is generally preferable where contamination control and grease retention are important. An open bearing may be suitable when external seals are already incorporated or when a special lubrication system is required. Sealed versions may have higher running torque.
What information produces the most accurate RB12025 quotation?
Provide the quantity, required accuracy, clearance or preload, seal arrangement, lubricant, operating loads, speed, mounting drawing, inspection-document requirements and destination. A complete specification reduces the risk of quoting an unsuitable configuration.
Request an RB12025 Quotation
Send the complete model designation, shaft and housing drawing, operating loads and accuracy requirements for technical confirmation. Email:sales@luoyangdeeplink.comPhone / WhatsApp / WeChat: +86 180 3700 3779 Website:www.lydl-bearing.com
THK, IKO, NSK and their respective product designations are trademarks or identifiers of their respective owners. They are mentioned only for technical identification and preliminary engineering comparison.
LYDL and Luoyang Deeplink Technology Co., Ltd. are independent and are not affiliated with, authorized by or endorsed by these manufacturers.
Final specifications, interchangeability, load calculations and mounting dimensions must be confirmed using the approved LYDL drawing and the customer’s actual operating conditions.
Final selection must consider the actual radial load, axial load, overturning moment, shock load, speed, operating cycle, required life, mounting rigidity, lubrication and acceptable running torque.
