Double-Row Cylindrical Roller Bearings

**NSK Super Precision Bearings: Engineered for Unmatched Accuracy and Performance**

In the world of high-precision motion and control, NSK’s **Super Precision Bearings** stand as a benchmark for reliability, rigidity, and ultra-low friction performance. Among these, the **Super Precision Cylindrical Roller Bearings** and **Double Row Cylindrical Roller Bearings** are engineered to meet the most demanding applications—delivering exceptional rotational accuracy, high load capacity, and extended service life in industries where precision is non-negotiable.

### **Technical Excellence and Design Innovations**
NSK’s **Super Precision Cylindrical Roller Bearings** are designed with optimized roller profiles, precision-ground raceways, and advanced materials to minimize vibration, heat generation, and wear. These bearings feature:
– **Ultra-High Precision (P4, P2, or higher grades)** – Ensuring minimal runout and consistent performance in high-speed applications.
– **Enhanced Load Capacity** – Radial load handling is maximized through superior roller-to-raceway contact, making them ideal for heavy-duty machining and automation.
– **Low Friction & High-Speed Capability** – Special cage designs (e.g., brass or polymer cages) reduce friction, allowing for smoother operation at elevated speeds.

For applications requiring even greater rigidity and load distribution, NSK’s **Double Row Cylindrical Roller Bearings** provide:
– **Increased Radial Stiffness** – Two rows of rollers enhance stability, critical for machine tool spindles and high-precision gearboxes.
– **Optimized Internal Geometry** – Precision alignment minimizes deflection under heavy loads, maintaining accuracy in dynamic conditions.
– **Sealed or Open Configurations** – Options for grease lubrication or integrated sealing solutions extend maintenance intervals in harsh environments.

### **Performance Advantages for Critical Applications**
NSK’s super precision cylindrical roller bearings excel in environments where even micron-level deviations can impact performance. Key advantages include:
– **Extended Service Life** – Advanced heat treatment and surface finishing techniques reduce wear, ensuring longevity even under continuous high-load operation.
– **Reduced Noise & Vibration** – Critical for semiconductor manufacturing, medical imaging equipment, and high-end robotics.
– **Thermal Stability** – Engineered to maintain dimensional stability under thermal fluctuations, crucial for CNC machining and aerospace components.

### **Typical Applications Across Industries**
These bearings are indispensable in sectors demanding the highest levels of precision and durability:
– **Industrial Machinery** – Machine tool spindles, robotic arms, and printing presses rely on their rigidity and speed capabilities.
– **Automotive Systems** – High-performance transmissions, electric vehicle (EV) drivetrains, and turbochargers benefit from their low friction and high-load support.
– **Precision Equipment** – Medical imaging devices, optical alignment systems, and semiconductor wafer handling require the near-zero runout provided by NSK’s super precision designs.

By combining cutting-edge engineering with decades of expertise, NSK’s **Super Precision Cylindrical Roller Bearings** and **Double Row Cylindrical Roller Bearings** set the standard for motion control in the most demanding applications—ensuring efficiency, accuracy, and reliability where it matters most.

MORE +
CLOSE +
Designations Nominal Dimensions Basic Load Ratings Speeds
Limiting Speeds
d
mm
D
mm
B
mm
r(min.)
mm
Cr
kN
C0r
kN
Grease
min-1
Oil (Oil-air)
min-1
NN3940MBKR
200
280
60
2.1
480
815
3200
3800
NN3948MBKR
240
320
60
2.1
525
975
2400
2900
NN3956MBKR
280
380
75
2.1
695
1460
2000
2500
NN4940MB
200
280
80
2.1
655
1220
3200
3800
NN4948MB
240
320
80
2.1
720
1450
2400
2900
NN4956
280
380
100
2.1
960
2230
2000
2500
NN3032MBKR
160
240
60
2.1
430
660
3800
4500
NN4936MBKR
180
250
69
2
550
1020
3500
4200
NNU4930MB
150
210
60
2
405
715
4200
5000
NN3032TB
160
240
60
2.1
430
660
4300
5000
NNU4936MB
180
250
69
2
550
1020
3500
4200
NNU4930MBKR
150
210
60
2
405
715
4200
5000
NN3032TBKR
160
240
60
2.1
430
660
4300
5000
NNU4936MBKR
180
250
69
2
550
1020
3500
4200
NN3030MB
150
225
56
2.1
385
585
4000
4800
NN3032ZTB
160
240
60
2.1
255
330
4500
6000
NN3036MB
180
280
74
2.1
650
995
3300
4000
NN3030MBKR
150
225
56
2.1
385
585
4000
4800
NN3032ZTBKR
160
240
60
2.1
255
330
4500
6000
NN3036MBKR
180
280
74
2.1
650
995
3300
4000
NN3030TB
150
225
56
2.1
385
585
4500
5300
NN3934MB
170
230
45
2
320
550
3800
4500
NN3938MB
190
260
52
2
395
680
3400
4000
NN3030TBKR
150
225
56
2.1
385
585
4500
5300