Precision Bearings
P4/P2 Grade | ABEC-7/9 | 10–500mm Bore
High-precision angular contact ball bearings, cylindrical roller bearings, spindle bearings, and thrust ball bearings engineered for demanding CNC machine tool spindle applications. ISO 9001:2015 certified manufacturing.
World-Class Precision Bearing Manufacturing
Luoyang Songju manufactures high-precision bearings to P4 and P2 accuracy grades (equivalent to ABEC-7 and ABEC-9), serving the most demanding spindle applications in CNC machining, grinding, milling, and turning operations.
Our precision bearings cover a bore range from 10mm to 500mm and are manufactured in our 22,000 m2 facility in Luoyang — China's historic bearing manufacturing hub. Every bearing undergoes rigorous inspection including dimensional accuracy, radial runout, axial runout, and vibration testing before shipment.
P4/P2 Grades
ISO 492 Class 4/2
ABEC-7/9
AFBMA equivalent grades
10–500mm Bore
Wide size coverage
ISO 9001:2015
Certified quality
Typical Applications
CNC Machining Center Spindles
High-speed precision spindle bearing arrangements for vertical and horizontal machining centers
Grinding Machine Spindles
Ultra-precision bearings for internal, external, and surface grinding spindles
Turning & Milling Spindles
High-rigidity bearing sets for heavy-duty turning centers and milling heads
Rotary Tables & Indexing Heads
Precision bearings for rotary axes with high positioning accuracy requirements
In-Stock Precision Bearing Models
Ready-to-ship precision bearings available from our Luoyang warehouse
ZKLF40100-2RS-2AP-XL
Double-direction axial angular contact ball bearing with double sealing. Designed for high-axial-load ball screw support bearing arrangements in precision machine tools. Pre-lubricated, ready to mount with bolt circle flange housing.
2-697920/P2 Gamet Bearing
Ultra-precision P2 grade bearing manufactured to Gamet specifications. Suitable for high-speed machine tool spindles requiring the highest accuracy class. Exceptional running accuracy and rigidity for finish-grinding and high-precision turning applications.
Precision Bearing Categories
Comprehensive range of high-precision bearings for every machine tool spindle requirement
Angular Contact Ball Bearings
P4 and P2 grade single-row angular contact ball bearings with 15 or 25 degree contact angle. Available as individual bearings or matched sets (DB, DF, DT arrangements) for machine tool spindles. Universal-face ground for interchangeable mounting. Precision cages in phenolic, PEEK, or machined brass.
Cylindrical Roller Bearings
P4 grade double-row and single-row cylindrical roller bearings designed for high radial rigidity in machine tool spindles. NN, NNU, and N types available. Suitable for the non-locating (floating) end of spindle arrangements. Optimized roller profile and cage design for minimum friction at high speeds.
Spindle Bearings
Ultra-precision bearings specifically engineered for milling, grinding, and turning spindles. Available as complete spindle bearing sets with preload and lubrication optimized for the target spindle speed range. Ceramic hybrid (Si3N4 balls) options available for high-speed applications up to 60,000 RPM and beyond.
Thrust Ball Bearings
Single-direction and double-direction thrust ball bearings with high axial load capacity. Designed to handle pure axial loads in vertical spindle arrangements, rotary tables, and lead screw support applications. Available with flat or spherical housing washers for self-alignment capability.
Every Bearing Inspected Before Shipment
Quality is at the core of our manufacturing process. Every precision bearing leaving our Luoyang facility undergoes a comprehensive inspection protocol to verify dimensional accuracy, running accuracy, and surface finish against ISO 492 and AFBMA standards.
Dimensional Inspection
Bore diameter, outer diameter, width, and chamfer dimensions verified with certified micrometers and CMM equipment
Running Accuracy Test
Radial runout (Kia/Kea) and axial runout (Sia/Sea) measured per ISO 492 to verify P4 or P2 grade compliance
Vibration & Noise Analysis
Bearing vibration velocity and noise level measured to ensure smooth operation at rated speeds
Surface Finish Verification
Raceway and rolling element surface roughness verified to Ra 0.025–0.05 micron for P2 grade bearings
Inspection Certificate Provided
Every bearing shipment includes a detailed inspection certificate documenting the measured values for each parameter. Traceability documentation is available upon request.
Why Choose Luoyang Songju Precision Bearings
Engineered for the most demanding spindle applications with measurable performance advantages
Sub-Micron Accuracy
P2 grade bearings achieve dimensional and running accuracy within sub-micron tolerances. Radial runout as low as 0.001mm for the highest precision applications in grinding and finishing spindles.
Optimized Heat Management
Precision-ground raceways and optimized ball/roller profiles reduce friction-generated heat. PEEK and phenolic cages provide thermal stability at sustained high speeds.
Extended Service Life
Premium bearing steels (100Cr6 / 52100) with controlled retained austenite content. Ceramic hybrid options using Si3N4 balls reduce wear and extend relubrication intervals up to 3x.
Universal Matching
Angular contact bearings are universally face-ground, allowing any combination of DB, DF, or DT mounting without shimming. Preload classes L, M, H available for each arrangement.
High Speed Capability
Ceramic hybrid bearing configurations with optimized internal design achieve DN values exceeding 2.0 million. Suitable for spindle speeds up to 60,000 RPM in controlled applications.
Global Interchangeability
Designed to ISO dimensional standards for direct interchange with major global bearing manufacturers. Drop-in replacement for NSK, SKF, FAG, INA, NTN, and Timken precision bearing series.
Need a Specific Precision Bearing?
Tell us your bearing requirements — bore size, accuracy grade, application, and quantity — and our engineering team will provide a competitive quotation within 24 hours.