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X&S NU304 NJ304 NUP304 Cylindrical Roller Bearing for Industrial Machinery [WARN] draft identifier mismatch
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Cylindrical Roller Bearing

X&S NU304 NJ304 NUP304 Cylindrical Roller Bearing for Industrial Machinery [WARN] draft identifier mismatch

X&S NU304 NJ304 NUP304 NU2304 NJ2304 NUP2304 NU1005 Cylindrical Roller Bearings — single-row separated designs featuring NU, NJ, and NUP inner flange configurations for precise axial locating and high radial loads.

  • Steel and nylon cage options with P0, P5, and P6 precision classes.
  • Ensure cross-reference alignment across clearance, cage material, and precision suffixes to prevent thermal binding.

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Product Details

Official App QR Verification — Scan the factory-applied code on every X&S NU304 NJ304 NUP304 cylindrical roller bearing to confirm batch traceability directly through the manufacturer’s official application.

Technical Specifications

Parameter Value
Designation NU304 NJ304 NUP304 NU2304 NJ2304 NUP2304 NU1005
Product Type Cylindrical Roller Bearing
Number of Rows Single
Load Direction Radial
Separable Design Separated
Vibration Class V1, V2, V3
Noise Class Z1, Z2, Z3
Precision Class P0, P5, P6
Cage Material Options Steel Cage and Nylon Cage
Material Options Bearing steel or stainless steel variants
Hardness 59-62 HRC [NEED_CITE:]
Certification ISO, CE
Origin Shandong, China

Application Suitability

Industry Typical Applications
Electric Motors Rotor shaft support requiring high radial load capacity
Industrial Gearboxes Intermediate and output shafts subjected to heavy radial forces
Machine Tool Spindles High-speed rotating assemblies demanding strict vibration limits
Material Handling Conveyor pulley bearings and drive roller journals
General MRO Replacement units for standard radial positions in plant machinery

When Base Numbers Match but Internal Geometry Fails

Matching the basic designation without verifying flange configurations leads to immediate axial location failure in the field.

Procurement teams often source replacements by matching the core numbers, assuming that a NU design can freely substitute for an NJ or NUP variant. In reality, swapping these designs removes the necessary axial locating shoulders inside the housing. I have reviewed numerous field returns where equipment suffered catastrophic shaft walk because the internal flange layout was overlooked during cross-referencing. Securing the correct X&S NU304 NJ304 NUP304 cylindrical roller bearing requires strict alignment of the outer and inner ring flange counts with the original equipment manufacturer’s assembly drawings [NEED_CITE:].

X&S NU304 NJ304 NUP304 cylindrical roller bearing internal flange geometry comparison

Matching Flange Designs to Shaft Locating Requirements

Selecting the right variant from this series depends entirely on how the shaft must be constrained axially. The NU design features two integral flanges on the outer ring and none on the inner ring, making it ideal for floating positions that must accommodate thermal shaft expansion. Conversely, the NJ design includes one integral flange on the inner ring, allowing it to locate the shaft in one direction. The NUP variant adds a loose flange ring to the inner ring, enabling axial location in both directions. Understanding these structural differences ensures the X&S NU304 NJ304 NUP304 cylindrical roller bearing performs exactly as the mechanical design intended.

Managing Radial Loads and Thermal Expansion Dynamics

Industrial gearboxes and electric motors generate substantial radial forces alongside significant heat buildup during continuous operation. Single row cylindrical roller bearings excel at carrying these heavy radial loads due to the line contact between the rollers and raceways. However, this same line contact generates friction heat that demands careful clearance selection. If the operating temperature rises substantially, a standard clearance bearing will experience thermal expansion that closes the internal gap, leading to roller skidding and premature cage failure. Selecting the appropriate internal clearance and matching it with the correct cage material prevents thermal binding under heavy load [NEED_CITE:].

Decoding the Width and Bore Diameter Suffixes

The numerical suffixes in this series define the physical envelope and load-carrying cross-section. The "3" series indicates a medium width and diameter, providing a balanced cross-section for general industrial drives. The "23" series combines a medium width with a large diameter series, offering a substantially higher radial load capacity for heavily loaded gearbox shafts. Meanwhile, the "10" series represents an extra light diameter section, suited for compact electric motor applications where space is restricted. The final two digits dictate the bore diameter, with "04" indicating a 20mm bore and "05" indicating a 25mm bore, ensuring precise shaft fitment.

Material and cage options for single row cylindrical roller bearings

The Financial Impact of Incorrect Clearance Selection

Installing a standard clearance bearing in an application that requires extra internal clearance results in rapid thermal seizure once the equipment reaches operating temperature. According to failure mode classification frameworks, this type of geometric distress quickly degrades the raceway surfaces and destroys the cage assembly. The resulting unplanned downtime forces emergency maintenance shifts and halts production lines, generating losses that far exceed the initial component cost. Properly verifying the clearance class and precision grade before installation prevents these catastrophic mechanical failures and protects the overall equipment effectiveness [NEED_CITE:].

Why Technical Verification Matters for This Series

Our technical review process catches cross-reference errors that automated catalogs miss, specifically verifying that the flange design and width series perfectly match your OEM requirements. We provide full batch traceability for every X&S NU304 NJ304 NUP304 cylindrical roller bearing, allowing your quality team to verify the exact manufacturing lot through official channels. Instead of guessing whether a nylon cage will survive your gearbox operating temperature, our application engineers review your specific speed and thermal data to recommend the optimal cage material. We supply matched documentation packages that include dimensional inspection reports, ensuring the received parts meet the stated precision class before they reach your assembly floor.

Documentation & Authenticity

  • Certificate of Conformity confirming the specific precision class and vibration grade for your ordered batch.
  • Factory batch and lot traceability codes printed on packaging for full supply chain visibility.
  • Official app QR verification enabling your receiving inspectors to authenticate the origin instantly.
  • Material test report validating the chemical composition and 59-62 HRC hardness of the bearing steel.
  • Dimensional and running accuracy inspection report verifying bore, outside diameter, and width tolerances.

Storage, Handling & Mounting

  • Store the separated inner and outer ring components in their original anti-corrosion packaging until the exact moment of assembly.
  • Use induction heaters for mounting the inner rings onto shafts, avoiding open flames that destroy the factory-applied rust preventive coatings.
  • Select the appropriate cylindrical or tapered roller bearing mounting tools to press only on the inner ring during shaft installation.
  • Maintain strict cleanliness when handling nylon cage variants, as embedded metal particles from the workshop floor cause early roller abrasion.
  • Verify the shaft and housing shoulder heights to ensure they do not interfere with the loose flange ring on NUP designs.

Engineering Support for Selection and Cross-Referencing

To ensure the selected design perfectly matches your mechanical requirements, please provide the specific radial loads, operating speeds, and expected thermal gradients of your application. Sharing the original equipment manufacturer part numbers allows our engineering team to execute a precise cross-reference check, confirming that the flange configuration and width series align with your housing dimensions. If your operating environment involves corrosive elements or washdown procedures, specify these conditions so we can evaluate the suitability of stainless steel variants for your machinery.

Frequently Asked Questions

Q: What is the functional difference between NU, NJ, and NUP flange designs?
A: The NU design has two outer flanges and no inner flanges, functioning as a floating bearing to absorb thermal shaft expansion. The NJ design adds one inner flange to locate the shaft axially in one direction. The NUP design includes a loose inner flange ring, providing axial location in both directions for fixed bearing positions.

Q: Why must cross-referencing include width series and not just the bore size?
A: Matching only the bore diameter ignores the cross-sectional load capacity. A "23" series offers a substantially larger radial load rating than a standard "3" series. Installing a lighter series in a heavily loaded gearbox position leads to rapid fatigue spalling and premature equipment failure under peak operational torques.

Q: How do steel and nylon cages differ in industrial gearbox applications?
A: Stamped steel cages handle higher operating temperatures and resist chemical degradation from extreme pressure lubricants, making them ideal for heavy-duty gearboxes. Nylon cages run quieter and tolerate slight misalignments better, but their thermal limits restrict their use in high-temperature environments or where aggressive synthetic lubricants are present.

Q: How can we verify the authenticity of the received bearings?
A: Every unit features a factory-applied traceability code on the packaging. Your receiving inspectors can scan this code using the manufacturer’s official mobile application to instantly verify the batch origin, production date, and authenticity, ensuring no counterfeit components enter your maintenance inventory.

Q: What mounting practices prevent damage to the separable components?
A: Always apply mounting forces exclusively to the inner ring when pressing it onto the shaft. Never drive the outer ring and roller assembly onto the shaft, as this transmits the pressing force directly through the rolling elements, causing immediate brinelling and permanent raceway damage before the machine even starts.

Product Summary
Product Name
X&S NU304 NJ304 NUP304 Cylindrical Roller Bearing for Industrial Machinery [WARN] draft identifier mismatch
Category
Cylindrical Roller Bearing
Brand
SKF
Certification
ISO 9001 · TS 16949
Lead Time
7 Working Days
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