The RU148 cross roller bearing is a reliable integrated bearing with a 90 mm bore, 210 mm outside diameter and 25 mm width. Its crossed cylindrical rollers support radial loads, bidirectional axial loads and overturning moments, while mounting holes on both rings simplify installation.
With dynamic and static radial load ratings of 49.1 kN and 76.8 kN, the RU148 cross roller bearing is suitable for robot positioners, medium-size robot joints, CNC rotary tables, inspection platforms and precision automation.
LYDL supplies RU148, RU148G and RU148X mounting configurations with open, one-side-sealed or double-sealed options. P5, P4 and P2 accuracy, controlled clearance or preload, optional grease nipples, custom lubrication and inspection reports are available on request.
RU148 Cross Roller Bearing Overview
The RU148 cross roller bearing is an integrated, mounting-holed precision bearing for rotary systems requiring a 90 mm hollow passage, a wider supporting diameter and greater combined-load capacity than RU124.
Its principal dimensions are 90 mm bore, 210 mm outside diameter and 25 mm width. Cylindrical rollers are arranged alternately at 90 degrees, enabling one bearing to support radial loads, axial loads in both directions and overturning moments.
As part of the RU series crossed roller bearings, the RU148 cross roller bearing has mounting holes machined directly into both rings. This can reduce separate housings and clamping flanges while providing a rigid and compact rotary support.
Key RU148 Advantages
Integrated inner and outer rings
90 mm hollow center passage
147.5 mm roller pitch diameter
49.1 kN dynamic radial load rating
76.8 kN static radial load rating
Twelve mounting positions on each ring
RU148, RU148G and RU148X hole configurations
Open, one-side-sealed and double-sealed options
Suitable for inner- or outer-ring rotation
RU148 Cross Roller Bearing Specifications
Parameter
RU148 Specification
Bearing type
Mounting-holed cross roller bearing
Ring construction
Integrated inner and outer rings
Bore diameter, d
90 mm
Outside diameter, D
210 mm
Width, B
25 mm
Roller pitch circle diameter, dp
147.5 mm
Minimum chamfer, r min.
1.5 mm
Greasing-hole diameter, d1
3.1 mm
Reference shoulder diameter, ds max.
133 mm
Reference housing shoulder diameter, Dh min.
162 mm
Inner-ring mounting PCD
112 mm
Outer-ring mounting PCD
187 mm
Basic dynamic radial load rating, C
49.1 kN
Basic static radial load rating, C₀
76.8 kN
Approximate mass
4.9 kg
Standard material
GCr15 / 100Cr6 bearing steel
Available accuracy
P5, P4 and P2
Supported load directions
Radial, bidirectional axial and moment
The stated RU148 cross roller bearing ratings are radial catalog values. They do not represent the permissible combined load or maximum overturning moment of the complete machine.
Bearing life and static safety should be calculated using the actual radial load, axial load, moment arm, speed, duty cycle, shock factor, preload, lubrication and mounting rigidity.
RU148 Cross Roller Bearing Design Characteristics
Wider Moment-Supporting Geometry
The 147.5 mm roller pitch diameter provides a wider load-supporting geometry than RU124. This makes RU148 a practical candidate for equipment carrying offset tooling, fixtures or robot payloads.
The allowable moment must still be calculated from the applied force and its distance from the bearing center. Bearing capacity alone does not account for mounting-plate or bolt-joint deformation.
90 mm Hollow Center
The bore provides space for a hollow reducer output, drive shaft, power cables, pneumatic lines or coolant connections. Clearance must be reserved for movement, protective sleeves and connector installation.
Twelve-Position Mounting Pattern
RU148 uses twelve equally spaced mounting positions on each ring. Compared with smaller RU models, the increased number of fastening points can distribute joint forces more evenly when the mounting plates are sufficiently rigid and accurately machined.
Integrated Ring Structure
Both rings are integrated, reducing sensitivity to ring separation during handling and installation. Direct mounting also helps limit the number of components and accumulated assembly tolerances.
View the complete cross roller bearing range when a split-ring structure or alternative mounting design is required.
RU148 Cross Roller Bearing Mounting Variants
All three RU148 versions share the same main dimensions, roller pitch diameter and reference load ratings. Their mounting-hole arrangements are different.
Inner- and outer-ring counterbores face the same direction
RU148G
12 × Ø9 through, Ø14 counterbore, depth 8.6
12 × Ø9 through, Ø14 counterbore, depth 8.6
Inner- and outer-ring counterbores face opposite directions
RU148X
12 × M8 threaded through
12 × Ø9 through, Ø14 counterbore, depth 8.6
Inner ring uses threaded holes
Selecting the Mounting Version
Choose RU148 when both fastening systems can be accessed from the same assembly side.
Choose RU148G when inner- and outer-ring fasteners must be inserted from opposite sides.
Choose RU148X when bolts need to engage directly with M8 threads in the inner ring.
Confirm the mounting version before machining the output flange, housing or bolt-access openings.
RU148 Seal, Clearance and Accuracy Codes
Code
Meaning
Application Note
No seal code
Open bearing
Clean equipment or external sealing
UU
Seals on both sides
Improved contamination protection and grease retention
U
Seal on one side
Seal on the outer-ring counterbore side
UT
Seal on one side
Seal opposite the outer-ring counterbore side
CC0
Negative clearance or controlled preload
Increased rigidity and positioning stability
C0
Positive radial clearance
Lower rotational resistance
C1
Positive clearance greater than C0
Application-specific clearance
P5
Precision grade
General precision automation
P4
High-precision grade
Robot positioners and rotary tables
P2
Ultra-high-precision grade
Metrology and demanding positioning systems
R
Outer-ring running accuracy controlled
Outer ring is the precision rotating ring
B
Both-ring running accuracy controlled
Either ring may be the precision rotating ring
-N
Optional grease nipple
Relubrication access required
Without an R or B designation, the standard model convention normally controls inner-ring rotational accuracy. Confirm the rotating ring and required runout before ordering.
A detailed configuration may be written as: RU148 / UU / CC0 / P4 / B / X / -N This identifies a double-sealed, preloaded, P4-grade RU148X with controlled running accuracy for both rings and an optional grease nipple.
The approved LYDL drawing and purchase order remain the final configuration authority.
RU148 Cross Roller Bearing Applications
Robot Positioners and Larger Robot Joints
RU148 can be considered for robot bases, shoulder joints, welding positioners and rotary axes carrying offset loads. Joint moment, emergency-stop loading and mounting stiffness should be reviewed before selection.
CNC Rotary and Tilting Tables
Its integrated structure and available preload make it suitable for indexing tables, inspection tables and rotary axes requiring rigidity and repeatable positioning.
Precision Assembly Platforms
The bearing can support rotary fixtures, assembly stations and automated tooling where both axial load and overturning moment are present.
Medical and Inspection Systems
The 90 mm passage can accommodate wiring and mechanical services in imaging modules, scanning systems and optical inspection platforms.
Select the RU124 cross roller bearing when an 80 mm passage and smaller 165 mm outside diameter are sufficient.
Select RU148 when the application requires a 90 mm passage, wider supporting geometry and higher load ratings than RU124.
Select the RU178 cross roller bearing when a 115 mm bore and substantially higher load capacity are necessary.
This comparison supports preliminary selection only. Use the cross roller bearing selection guide and an application-specific life and rigidity analysis before confirming the bearing.
These references indicate a similar 90 × 210 × 25 mm envelope and mounting concept. They do not establish automatic interchangeability.
For example, some IKO CRBFV9025 references specify a 12 mm outer-ring counterbore depth, while the RU148 reference design uses 8.6 mm. Catalog load ratings can also differ because of internal design and rating methodology.
Before approving a replacement, compare:
Complete dimensional drawing
Inner- and outer-ring PCDs
Counterbore depth and direction
M8 thread configuration
Mounting shoulder dimensions
Seal arrangement
Accuracy and controlled rotating ring
Clearance or preload
Starting and running torque
Load ratings and lubrication
THK and IKO are trademarks of their respective owners. They are mentioned only for model identification and technical comparison. LYDL is an independent manufacturer and is not affiliated with or endorsed by these companies.
Engineering Standards Relevant to RU148
ISO 281 provides general methods for dynamic load ratings and basic rating-life calculations.
ISO 76 covers static load ratings, static equivalent loads and static safety evaluation.
ISO 492 provides general dimensional and geometrical tolerance terminology for radial rolling bearings.
ISO 15243 standardizes terminology for bearing damage, characteristics and possible failure causes.
These standards provide calculation and terminology frameworks. They do not replace RU148 catalog data, the approved LYDL drawing or application-specific engineering analysis.
RU148 Cross Roller Bearing Installation
Because RU148 is often used with substantial overturning moment, mounting-plate rigidity is as important as bearing accuracy.
Clean the bearing and both mounting faces.
Remove burrs from shoulders, through holes and counterbores.
Confirm the 112 mm and 187 mm mounting PCDs.
Verify whether RU148, RU148G or RU148X is required.
Check the direction and depth of every counterbore.
For RU148X, confirm M8 bolt engagement without bottoming out.
Lower the bearing into position without hammering or impact.
Install all twelve fasteners loosely before final tightening.
Tighten the fasteners gradually in a diagonal sequence.
Rotate the bearing during staged tightening.
Measure axial and radial runout after installation.
Confirm running torque and temperature during initial operation.
Do not apply one universal bolt torque to every application. The correct value depends on bolt grade, thread engagement, supporting material, surface treatment and lubrication condition.
If the mounting plate deflects under the applied moment, a higher bearing accuracy grade alone will not correct the resulting system error.
RU148 Cross Roller Bearing Inspection and Packaging
LYDL can inspect RU148 according to the selected mounting version, accuracy, preload and documentation requirements.
Available Inspection Items
Bore, outside diameter and width
Mounting-hole position and PCD
Counterbore diameter, depth and orientation
M8 thread inspection for RU148X
Ring roundness and raceway geometry
Material hardness
Radial clearance or preload
Starting and running torque
Radial and axial runout
Rotation smoothness and noise
Seal, model and serial-number verification
Inspection reports, material certificates and traceability records can be supplied when requested before production.
After inspection, each bearing receives suitable anti-rust protection. Packaging options include sealed or vacuum bags, shock-resistant material, individual cartons and reinforced export plywood cases.
Why Source an RU148 Cross Roller Bearing From LYDL?
LYDL manufactures precision crossed roller bearings in Luoyang, China. Production and inspection capabilities cover ring machining, heat treatment, raceway grinding, superfinishing, component sorting, cleaning, assembly, preload verification and final inspection.
Available RU148 options include:
RU148, RU148G and RU148X mounting designs
Open, U, UT and UU sealing
P5, P4 and P2 accuracy
Inner-ring, outer-ring or both-ring accuracy control
Controlled clearance or preload
Special grease and optional grease nipple
OEM marking and serial numbers
Material and dimensional reports
RU148 Cross Roller Bearing FAQ
How does mounting-plate stiffness affect RU148 performance?
A flexible plate can distort under overturning moment, changing load distribution and installed runout. The plate, bolt circle and bearing should therefore be evaluated as one structural system.
Why does RU148 use twelve mounting positions?
The twelve-position pattern helps distribute mounting and operating forces around the rings. It does not compensate for an uneven surface or incorrectly tightened fasteners.
When is RU148G preferable to standard RU148?
RU148G is preferable when the inner- and outer-ring fasteners must be inserted from opposite assembly sides. This should be decided before surrounding components are machined.
Can RU148 carry a long cantilevered fixture?
It can resist moment loading, but the applied moment increases with fixture weight and distance from the bearing center. Bearing life, static safety, bolt loading and plate deflection must all be checked.
Is RU148 intended for continuous high-speed rotation?
RU148 is primarily designed for rigidity, combined loads and precision positioning. Continuous speed capability depends on load, preload, seals, grease, heat dissipation and acceptable temperature rise.
Why can CRBFV9025AT not always replace RU148X directly?
Although the main dimensions and M8 inner-ring concept are similar, counterbore depth, load ratings, tolerances, seals and internal specifications may differ. Compare approved drawings before replacement.
When should RU178 be selected instead of RU148?
RU178 should be considered when the application requires a 115 mm bore or substantially higher dynamic and static load ratings. RU148 remains more compact and lighter.
Request a Reliable RU148 Cross Roller Bearing Quote
For accurate selection and pricing, provide the quantity, mounting version, seal arrangement, rotating ring, radial and axial loads, moment arm, speed, duty cycle, accuracy, preload, lubricant and inspection requirements. Contact the LYDL engineering team for an RU148 drawing, variant confirmation, application review, production lead time and export quotation.
These references support dimensional comparison, terminology and general calculation principles. They do not replace the approved LYDL drawing, inspection agreement or application-specific engineering review.
