INDICATIVE DESCRIPTION

Cylindrical roller bearing NNU4930B/SPW33, Super-precision

Super-precision double row cylindrical roller bearing with lubrication feature

Super-precision double row cylindrical roller bearings NNU4930B/SPW33 in the NNU 49 series are designed to accommodate heavy radial loads and high speeds, while providing a high degree of stiffness.

Having three flanges on the outer ring and no flanges on the inner ring, the bearings can accommodate axial displacement in both directions.

The separable design simplifies mounting and dismounting, particularly when load conditions require both rings to have an interference fit.

Key features of cylindrical roller bearings NNU4930B/SPW33

• High radial load carrying capacity
• Very high rigidity and high running accuracy
• Minimize noise, vibration and heat generation

High-precision bearings – Technical details by brand

The high-precision bearings offered by Texime are designed to deliver exceptional dimensional stability, smooth rotation, and extreme accuracy in the most demanding applications — such as machine tool spindles, high-speed motors, and measurement or automation systems.

Discover below the contact angles and cage types used by the main manufacturers.

1. Contact Angles

The contact angle determines a bearing’s ability to support axial loads and its maximum speed.
The smaller the angle, the higher the permissible rotational speed.
Each manufacturer uses its own designations.

FAG

• C = 15°
• D = 20°
• E = 25°
• B = 40°

For more information, please refer to the Schaeffler high-precision bearing catalog.

NSK (Series 70xx / 72xx / 79xx)

• C = 15°
• AS = 25°
• A = 30°

SKF

• CD = 15°
• AC = 25°
• F = 18°
• AB = 20° (for series 70 A and 719 A)

RHP

• E = 25°

SNFA

• 1 = CD = 15°
• 3 = AC = 25°

SNR/NTN

• C = 15°
• H, AD = 25°
• B = 40°

2. Cage Types

The cage retains the rolling elements and influences the bearing’s speed capacity, thermal resistance, and durability.
Each manufacturer uses its own cage designations.

FAG

• TVP = Plastic
• T = Laminated fabric

NSK

• TR = Phenolic resin
• MB = Brass cage
• TB = PPS

SKF

• For further details, please refer to the SKF high-precision bearing catalog.

RHP

• T = phenolic

SNFA

• C = Phenolic resin

SNR/NTN

• T1, G1 = phenolic
• T2 = polyamide
• V = laminated phenolic

Fafnir

• CR = phenolic

Typical Applications

These high-precision bearings are ideally suited for:

• Machine tools and milling spindles

• Measuring equipment and robotics

• Precision electric motors

• Industrial transmission systems

• Accommodate axial displacement in both directions

• Lubrication feature

• Thin section enabling compact application design