Wholesale NU Series Cylindrical Roller Bearings

NU Series Cylindrical Roller Bearings – Precision Radial Load Solutions

Shanghai Yinin Bearing & Transmission Company is a wholesale NU Series cylindrical roller bearings manufacturer and supplier based in China. Since 1999, we have evolved from representing domestic bearing brands to operating an integrated sales and manufacturing group, with our own factory in Jiangsu Province. Our NU Series range is designed for applications demanding high radial load capacity, high speed, and low friction, such as machine tool spindles, gearboxes, electric motors, and industrial pumps.

We supply NU1000, NU200, NU2200, NU300, and NU2300 series, each engineered with precision-ground rollers and raceways to ensure consistent performance and long service life. As a factory-direct source, we provide competitive wholesale pricing, flexible batch sizes, and technical support from selection through installation.

Understanding NU Series Bearing Design

NU series cylindrical roller bearings feature a single row of cylindrical rollers guided between two integral flanges on the inner ring, while the outer ring has no flanges. This design allows axial displacement of the shaft relative to the housing, accommodating thermal expansion and preventing axial load transmission. The line contact between rollers and raceways delivers high radial load capacity and stiffness, making NU bearings ideal for heavy radial loads at moderate to high speeds.

Compared to NJ, NUP, N, and NF series, NU bearings are the most common choice for free-side (non-locating) positions in bearing arrangements. They are available in open designs, with or without cages, and can be supplied with various cage materials including steel, brass, or polyamide, depending on operating conditions.

Our NU Series Product Range

We manufacture five primary NU series groups, each covering a range of bore sizes and load ratings. The table below summarizes the series and their typical applications.

We also offer custom dimensions and non-standard designs for OEM projects, produced in our own factory with full traceability.

Materials and Manufacturing Quality

Our NU series bearings are manufactured from high-grade alloy steel, typically GCr15 (AISI 52100), heat-treated to achieve uniform hardness and wear resistance. For corrosive environments, we can supply stainless steel variants. Rollers and raceways are precision-ground and super-finished to minimize friction and noise, while cages are selected based on speed, temperature, and lubrication requirements.

Quality control is integrated at every stage: incoming material inspection, in-process dimensional checks, and final testing for vibration, noise, and geometry. We perform 100% inspection on finished bearings according to customer specifications and international standards, ensuring dimensional accuracy and running precision.

Configuration and Customization Options

We understand that standard catalogs do not cover every application. Our engineering team works with you to configure the right bearing for your operating conditions. Key parameters we consider include:

• Radial load, axial load (if any), and combined load conditions
• Rotational speed and required speed rating
• Operating temperature range and lubrication method (grease or oil)
• Mounting arrangement (free side, locating side, or paired)
• Required precision class (P0, P6, P5, or higher)
• Internal clearance (C2, CN, C3, C4)
• Cage material and design
• Special coatings or dimensional modifications

For high-volume wholesale orders, we can optimize production to reduce lead times while maintaining strict quality standards. Our minimum order quantity is flexible, starting from as low as 100 sets for standard items.

Application Fit and Integration Support

NU series bearings are used across industries including automotive, agriculture, construction, mining, and renewable energy. In machine tool spindles, they provide high stiffness and accuracy; in gearboxes, they handle heavy radial loads with minimal heat generation; in electric motors, they ensure quiet, reliable operation.

We provide mounting and installation guidance to prevent premature failure. Our technical team can advise on shaft and housing fits, lubrication selection, and sealing arrangements. For automated production lines, we ensure consistent bearing quality to minimize downtime.

Quality Assurance and Testing

Each production batch undergoes rigorous inspection. We measure bore, outside diameter, width, radial runout, and surface finish using calibrated instruments. Vibration and noise tests are performed to ensure smooth operation. We also conduct dimensional and material verification to confirm compliance with your specifications.

Our factory is equipped with modern manufacturing and testing equipment, and we maintain a dedicated quality control center. We can provide inspection reports and certificates upon request, ensuring full traceability from raw material to finished product.

Packaging, Documentation, and Delivery

Bearings are individually wrapped in anti-rust paper, packed in boxes, and then in export cartons or wooden crates, depending on size and quantity. We provide standard export documentation including packing list, commercial invoice, and bill of lading. For special requirements, we can arrange certificates of origin or other documents.

Our warehouse in Jiangsu ensures efficient handling of both stock and production orders. In-stock items can be shipped within 3 working days, while production orders are scheduled based on quantity and complexity.

Information We Use to Configure Your Solution

To prepare an accurate quotation and technical proposal, please provide the following details:

• Bearing series and bore size, or exact part number
• Required quantity and target delivery date
• Application description (machine type, operating conditions)
• Radial and axial loads, speed, and temperature
• Required precision class and internal clearance
• Lubrication and sealing preferences
• Any special packaging or marking requirements

With this information, we can recommend the most suitable NU series bearing and provide a competitive wholesale quote.

FAQs

What is the difference between NU and NJ series bearings?

NU bearings have flanges on the inner ring only, allowing axial displacement in both directions. NJ bearings have flanges on both inner and outer rings on one side, providing axial location in one direction. Choose NU for free-side positions and NJ for locating positions.

Can you supply bearings with special precision classes?

Yes, we can manufacture NU series bearings to P6, P5, and higher precision classes upon request. We adjust grinding and finishing processes to meet tighter tolerances.

What is your minimum order quantity for wholesale?

Our standard MOQ is 100 sets for many sizes, but we can accommodate smaller trial orders for new customers. For large wholesale orders, we offer volume-based pricing.

Do you provide technical support for bearing selection?

Yes, our engineering team assists with bearing selection, fit recommendations, and troubleshooting. We can review your application data and suggest the optimal NU series configuration.

How do you ensure consistent quality across large orders?

We implement strict incoming material inspection, in-process checks, and final 100% inspection. Our quality system follows international standards, and we can provide test reports for each batch.

What are your typical lead times?

For stock items, we ship within 3 working days. For production orders, lead time depends on quantity and customization, typically 2-4 weeks. We confirm exact schedules when you place an order.