Frequently Asked Questions about the NTN 7319B Angular Contact Ball Bearing (40° Contact Angle, 95 × 200 × 45 mm):

Q1. What is the NTN 7319B angular contact ball bearing?

The NTN 7319B is a single-row angular contact ball bearing designed to withstand combined radial and axial loads, with a predominant axial component. It features a 40° contact angle and is commonly installed in pairs for enhanced rigidity and axial load support in machine tool spindles and precision equipment.

Q2. What are the main technical specifications of the 7319B?

Data from NTN official catalogs.

Q3. What advantages does a 40° contact angle provide?

A 40° contact angle increases the axial load capacity compared to lower-angle bearings. It translates radial forces into larger axial support and, when bearings are paired back-to-back (DB) or face-to-face (DF), delivers high stiffness and precise axial positioning in both directions.

Q4. What load ratings should I expect?

The 7319B offers a basic dynamic load rating of 167 000 N under operation and a basic static load rating of 149 000 N for stationary or shock load conditions.

Q5. What are the speed limits for the 7319B?

When lubricated with grease, its maximum speed is 3 200 rpm. Switching to oil lubrication raises the limit to 4 200 rpm, reducing frictional heat at high speeds.

Q6. What materials and cage design are used?

The bearing rings and balls are made of high-carbon chrome steel for hardness and wear resistance. A pressed steel cage maintains ball spacing and alignment under heavy loads and elevated temperatures.

Q7. Is the NTN 7319B separable?

Single-row angular contact bearings like the 7319B are non-separable, meaning the inner ring, outer ring, and cage form a single assembly. This simplifies installation but requires precise shaft and housing fits.

Q8. In which applications is the 7319B commonly used?

Machine tool spindles (CNC lathes, milling machines)

Hydraulic pumps and motors

Gearboxes requiring high axial rigidity

Screw drive and ball screw support units

Q9. How should I mount and preload this bearing?

For unidirectional axial loads, use a single bearing.

For bidirectional axial loads, mount two bearings in DB or DF configurations.

Apply the manufacturer’s recommended axial preload and torque the locking nuts to avoid ring distortion.

Q10. What lubrication and maintenance practices are recommended?

Use multi-purpose grease rated to 100 °C or ISO VG 32–68 oils for high-speed use.

Relubricate every 1 000–2 000 operating hours or when noise or temperature rises.

Keep the environment clean and monitor bearing temperature for signs of lubrication breakdown.

Q11. Why choose NTN over other brands?

NTN is known for precision engineering, consistent quality, and an extensive global distribution network. Their technical support helps you select the optimal bearing for your application and ensures reliable performance.

Q12. How do I select the right angular contact bearing?

Consider your application’s:

Load types (radial, axial, or combined)

Operating speeds and temperatures

Required stiffness and space constraints

Lubrication method and maintenance intervals

For detailed selection guidance, consult NTN engineering manuals or contact an NTN specialist/ QTE Technologies.