Double Row Cylindrical Roller Bearing NNU4921 B/Sp W33 for Heavy Duty Machinery
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P0-P4

Precision

1 PC

Min. Order

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Double Row Cylindrical Roller Bearing NNU4921 B/Sp W33 for Heavy Duty Machinery

Ensure smooth, high-load operation in heavy duty machinery with the Double Row Cylindrical Roller Bearing NNU4921 B/Sp W33, engineered to deliver exceptional durability and precision for industrial equipment. Crafted from high-grade bearing steel with a hardness of 60-64 HRC, this 120-190mm medium-large bearing handles axial loads effortlessly while maintaining stable performance under rigorous conditions.

  • Separated design allows easy installation and maintenance, reducing downtime for your machinery
  • Available clearance options (C0-C5) and vibration grades (Z1V1-Z3V3) ensure optimal customization for specific industrial needs
  • Brass or steel cage construction enhances wear resistance, extending service life in demanding applications

MOQ

1 Piece

Lead Time

5-15 Days

Warranty

12 Mo.

Precision

P0-P4

Noise Grade

Z2-Z4

Customization

OEM/ODM

  • High-grade chrome steel for long service life
  • Strict raw material inspection & full process monitoring
  • ISO 9001:2015 & ISO 14001 certified
  • ABMA & DIN standards compliant
  • Free samples for qualified distributors
  • T/T, Credit Card & Alibaba payment accepted

Product Details

Product Specifications

Parameter Details
Model Designation NNU4921 B/Sp W33
Type Double Row Cylindrical Roller Bearing
Outer Dimension Range 120-190mm
Material Bearing Steel
Alignment Capability Non-Aligning Bearings
Load Direction Axial Bearing
Separability Separated
Radial Clearance C0, C2, C3, C4, C5
Cage Material Brass, Steel
Vibration Grade Z1V1, Z2V2, Z3V3
Hardness 60-64 HRC
Transport Package Carton Pallet
HS Code 8482800000

Application Industries

Industry Typical Equipment
Industrial Machinery CNC Machine Tools, Gearboxes, Reducers
Heavy Duty Manufacturing Rolling Mills, Printing Presses, Crushers
Agricultural Machinery Tractors, Harvesters, Heavy Duty Tillers
Construction Equipment Excavators, Loaders, Conveyors
New Energy Wind Turbine Gearboxes, Solar Tracking Systems

Eliminate Downtime with Reliable NNU4921 B/Sp W33 Double Row Cylindrical Roller Bearings

Equipment failures caused by substandard bearings cost manufacturers thousands in lost production each year. When bearings fail prematurely in heavy duty machinery, the resulting downtime disrupts schedules, increases maintenance costs, and damages critical equipment components. Sourcing genuine, high-precision bearings that meet exact specifications remains a persistent challenge for industrial buyers.

Engineered for Heavy Load Applications in Demanding Environments

The NNU4921 B/Sp W33 double row cylindrical roller bearing delivers exceptional performance in heavy duty machinery operating under high radial loads. With decades of manufacturing experience, we produce these bearings to P0-P4 precision grades and Z2-Z4 noise standards, ensuring compatibility with industrial equipment requiring reliable rotation under extreme conditions. Our one-stop service integrates independent R&D and strict quality control, providing bearings that maintain stability in gearboxes, rolling mills, and construction machinery.

Optimal Performance in High-Stress Industrial Conditions

This double row cylindrical roller bearing excels in applications involving heavy radial loads and moderate axial loads, common in industrial gearboxes and large electric motors. Its separated design allows for easy mounting and dismounting, simplifying maintenance procedures. The W33 designation indicates a cylindrical outer ring with lubrication grooves and holes, ensuring efficient lubricant distribution even at high operating temperatures. When paired with proper lubrication, this bearing maintains performance in environments with continuous operation and variable load conditions.

Technical Features That Ensure Long Service Life

The bearing’s 60-64 HRC hardness provides exceptional wear resistance, critical for extending service life in abrasive environments. Available radial clearances (C0-C5) allow precise matching to specific operating conditions—tighter clearances (C2) for high-precision applications like CNC spindles, while larger clearances (C4-C5) accommodate thermal expansion in high-temperature equipment. Brass and steel cage options offer distinct advantages: brass cages provide superior strength for shock-loaded applications, while steel cages optimize performance in high-speed rotating equipment. Vibration grades Z1V1 to Z3V3 ensure smooth operation, reducing noise and minimizing equipment fatigue.

Total Cost of Ownership: Why Quality Matters More Than Price

Choosing lower-quality bearings may reduce initial costs, but frequently leads to higher long-term expenses. Counterfeit bearings often fail within 30-50% of the expected service life, requiring unplanned maintenance and production stoppages. Our NNU4921 B/Sp W33 bearings meet ISO, ABMA, and DIN international standards, ensuring consistent performance and predictable service intervals. Each bearing undergoes dimensional inspection and vibration testing in our in-house laboratory, verifying compliance with strict quality criteria. The result is a heavy duty machinery bearing that delivers reliable performance, reducing total ownership costs through extended service life and minimized downtime.

Our Commitment to Reliable Bearing Solutions

As a professional bearing manufacturer since 2005, we maintain ISO 9001:2015 quality management and ISO 14001 environmental management certifications. Our technical R&D team and experienced QC staff ensure every bearing meets exact specifications before shipment. We offer flexible order policies with 1 piece MOQ for standard bearings and 3-5 working day delivery for sample orders, supporting both emergency maintenance and scheduled production needs. Our 12-month warranty covers manufacturing defects, with free replacement or refund options available. Professional technical support includes bearing selection guidance, installation assistance, and remote troubleshooting to optimize bearing performance in your specific application.

Packaging & Shipping

  • Secure carton packaging with pallet reinforcement for bulk orders
  • Sample orders shipped within 3-5 working days
  • Bulk orders delivered in 5-15 working days
  • Multiple logistics options including DHL, FedEx, UPS, air, and sea freight
  • Real-time tracking provided for all shipments
  • 1 piece minimum order quantity available for emergency replacement

Get Your NNU4921 B/Sp W33 Bearing Today

Don’t let equipment downtime impact your production schedule. Contact us with your bearing requirements, application details, and quantity needs to receive a prompt quotation. Our inventory includes standard configurations for immediate shipment, ensuring you can resume operations with minimal delay.

Frequently Asked Questions

Q: Are these bearings genuine and traceable?

A: Yes, all our bearings are manufactured in-house under strict quality control processes. Each product can be traced through our production records, and we provide certification of compliance with international standards upon request.

Q: How do I confirm if this bearing fits my equipment?

A: Provide your equipment model, application requirements, and operating conditions (load, speed, temperature) to our technical team. We offer free选型 assistance to ensure proper bearing selection.

Q: What is the warranty period for this bearing?

A: We provide a 12-month warranty from the date of delivery, covering manufacturing defects. Defective products will be replaced free of charge or refunded according to customer preference.

Q: What is the minimum order quantity?

A: The minimum order quantity for standard bearings is 1 piece, supporting emergency maintenance needs. Customized orders have negotiable quantity requirements based on specifications.

Q: How quickly can you ship this bearing?

A: Standard bearings are available for immediate shipment, with delivery within 3-5 working days for sample orders and 5-15 working days for bulk quantities depending on order size.

Q: How can I verify the authenticity of the bearing?

A: Our bearings include production batch numbers that can be verified through our customer service team. Each shipment includes a quality inspection report confirming compliance with stated specifications.

Ready to order or need

Tags: Cylindrical Roller Bearing 120-190mm Cylindrical Roller Bearing W33 Double Row Bearing for Industrial Equipment Double Row Cylindrical Roller Bearing Heavy Duty Machinery Bearing High Precision Double Row Cylindrical Bearing NNU4921 B/Sp W33 NNU4921 Bearing for Heavy Load
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