QJ 248 N2MA
Four-Point Contact Bearings Ball Bearings
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Part No.
Part No.
QJ 248 N2MA
Basic Information
Bearing type
Ball
System of measurement
Metric
Construction
Single Row
Weight
53.2 kg
Tolerance class
P6 (ABEC-3)
Seal type
Open
For load direction
Four Point Contact
Main Dimensions
Bore diameter
240 mm
Bore diameter tolerance
-0.022mm to 0
Outside diameter
440 mm
Outside diameter tolerance
-0.033mm to 0
Width
72 mm
Width tolerance
-0.05mm to 0
Chamfer dimension
4 mm
Distance from side face to load point
238 mm
Inner Ring Dimensions
Inner ring large-side shoulder diameter
315 mm
Outer Ring Dimensions
Shoulder diameter outer ring
365 mm
Performance
Temperature range
-30° to 110 °C
Radial dynamic load rating
146250 lbf
Radial static load rating
270000 lbf
Limiting speed
2.4 X 1000 rpm
Lubrication
Lubricated
Materials
Ring material
Chrome Steel
Ball material
Chrome Steel
Cage material
Brass
Environment & Compliance
REACH
Compliant
ROHS
Compliant
Technical Drawings
No drawings available at the moment, will be launched soon
Price:
$ 2638.86
/ each
In Stock
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QJ 248 N2MA Bearing Product Overview & Core Advantages
The QJ 248 N2MA is a metric four-point contact ball bearing engineered for demanding applications requiring exceptional load handling capabilities. This single-row bearing is distinguished by its ability to simultaneously support substantial radial loads and axial loads from both directions, effectively functioning as a pair of back-to-back angular contact bearings. Manufactured to a P6 (ABEC-3) tolerance class, it delivers high running accuracy and reliability. Its compact design, combined with a high load rating, makes it an optimal solution for space-constrained, high-performance machinery.
QJ 248 N2MA Bearing Model Code Explained, Specifications & Naming Convention
| Suffix | Technical Meaning |
|---|---|
| N2 | Indicates the bearing has two machined grooves in the outer ring for securing snap rings, enhancing axial location and mounting security. |
| MA | Signifies that the bearing is pre-lubricated with a specific high-performance grease suitable for the specified temperature range. |
QJ 248 N2MA Bearing Structural Features & Performance Benefits
- Four-Point Contact Design: The unique raceway geometry allows the bearing to handle combined loads (radial and axial loads in both directions) with a single bearing row, offering a compact and simplified design compared to traditional duplex pairs.
- High Load Capacity: With a dynamic load rating of 146,250 lbf and a static load rating of 270,000 lbf, this bearing is built for heavy-duty applications and long service life under significant stress.
- Precision & Rigidity: The P6 tolerance class ensures precise internal geometry and smooth operation, while the solid construction provides high rigidity for stable performance.
- Optimized for Mounting: The N2 suffix with snap ring grooves facilitates easier and more secure installation, preventing creep in the housing.
- Ready-to-Use Lubrication: The pre-applied grease (MA) ensures immediate operation and provides initial protection, suitable for a wide temperature range of -30°C to 110°C.
QJ 248 N2MA Bearing Typical Application Areas
This bearing is ideally suited for heavy machinery and precision equipment where high load capacity and compactness are critical. Key sectors include:
- Industrial Gearboxes and large power transmission systems.
- Heavy-Duty Pumps and Compressors.
- Construction and Mining Equipment swing rings and slewing mechanisms.
- Large Machine Tool components, such as rotary tables and indexing heads.
- Material Handling and turntable systems.
