NTN NA4920C3 100x140x40 Needle Roller Bearing

NTN NA4920C3 100x140x40 Needle Roller Bearing

NTN NA4920C3 is a single-row machined-ring needle roller bearing with an inner ring, with nominal dimensions of 100x140x40 mm. The principal dimensions are d = 100 mm, D = 140 mm and C = 40 mm, while the roller-under diameter is F = 115 mm. The C3 suffix identifies a version with radial internal clearance greater than the Normal clearance class.

NTN NA4920C3 - Technical Characteristics

Key identification data:

Brand: NTN

Designation: NA4920C3

Base designation: NA4920

Bearing type: Needle roller bearing

Design: Machined-ring needle roller bearing with inner ring

Number of rows: Single row

Inner ring: Yes

Bore diameter d: 100 mm

Outside diameter D: 140 mm

Width C: 40 mm

Roller-under diameter F: 115 mm

Dimensions: 100x140x40 mm

Radial internal clearance: C3 - greater than Normal

The key technical identification is:

NTN + NA4920C3 + 100x140x40 mm + inner ring + C3 clearance

The complete designation should be retained when selecting a replacement because the C3 clearance is an integral part of the specification.

NTN NA4920C3 Dimensions

For the NA4920 design, NTN specifies:

d = 100 mm - bore diameter

D = 140 mm - outside diameter

C = 40 mm - bearing / outer-ring width

F = 115 mm - roller-under diameter

rs min = 1.1 mm - minimum chamfer dimension

Complete commercial dimensions:

100x140x40 mm

Unlike the corresponding RNA design, NA4920 has its own inner ring. Therefore, the 100 mm dimension is the actual nominal bearing bore d.

NA4920 Bearing Design

NTN classifies NA4920 as a:

Needle Roller Bearing, Machined-Ring, With Inner Ring

The bearing incorporates:

solid machined outer ring

separate inner ring

single row of needle rollers

roller cage

The needle rollers have a small diameter relative to their length, allowing high radial load capacity within a relatively compact radial cross-section.

Because NA4920 includes an inner ring, it can be used where the shaft itself is not intended to function directly as the needle-roller raceway.

Radial Load Capacity

Needle roller bearings use long, small-diameter rolling elements.

The line-contact geometry between the needle rollers and raceways provides high radial load capacity relative to the radial installation space.

For the official base NTN NA4920 design, NTN specifies:

Cr = 127 kN - basic dynamic radial load rating

C0r = 260 kN - basic static radial load rating

These ratings apply to the NA4920 base bearing geometry.

C3 Radial Internal Clearance

The suffix:

C3

identifies radial internal clearance greater than Normal.

This is the key distinction between the standard base reference and the requested variant:

NA4920 - standard catalogue version with Normal clearance

NA4920C3 - increased radial internal clearance C3

The C3 suffix should therefore not be omitted when ordering a replacement.

C3 does not describe the final operating clearance after installation. Actual operating clearance is also affected by shaft and housing fits, temperature differences, thermal expansion and operating conditions.

NA4920C3 vs NA4920

Both references use the same basic bearing size:

100x140x40 mm

The important difference is the radial internal clearance specification.

NA4920: base catalogue version

NA4920C3: C3 radial internal clearance, greater than Normal

A standard NA4920 should therefore not automatically be substituted when the original bearing specification explicitly requires C3.

NA4920 vs RNA4920

The NA and RNA configurations are technically different.

NA4920 - with inner ring

RNA4920 - without inner ring

For NA4920:

d = 100 mm

For the corresponding construction without an inner ring, the roller-under/raceway diameter becomes the critical internal dimension.

Therefore, NA4920 and RNA4920 should not be treated as identical complete bearing units.

Lubrication Hole

The official NTN specification for the NA4920 base design identifies:

Lubrication hole in outer ring: Yes

Lubrication-hole diameter k: 3.5 mm

Lubrication hole in inner ring: No

The lubrication hole in the outer ring can be used to supply lubricant to the bearing when incorporated into an appropriately designed housing and lubrication system.

Speed Ratings

For the base NTN NA4920 design, the manufacturer specifies:

2300 rpm - limiting speed with grease lubrication

3500 rpm - limiting speed with oil lubrication

These are catalogue values.

Actual permissible operating speed also depends on load, lubrication, bearing fits, temperature, heat dissipation and the complete bearing arrangement.

Operating Temperature

The official NTN product data for the base NA4920 design specify:

Minimum operating temperature: -20°C

Maximum operating temperature: +120°C

The temperature range should be considered together with the lubrication system and other operating conditions of the application.

Axial Displacement

NTN specifies:

s = 2 mm - maximum axial displacement

for the base NA4920 construction.

This value is a construction parameter and should not be interpreted as bearing axial internal clearance.

Selection and Interchangeability

When selecting a replacement for NTN NA4920C3, verify at least:

Complete designation NA4920C3

d = 100 mm

D = 140 mm

C = 40 mm

F = 115 mm

Machined-ring construction

Inner ring included

Single-row needle roller design

C3 radial internal clearance

Required radial load capacity

Operating speed

Lubrication conditions

Shaft and housing fits

A needle roller bearing measuring 100x140x40 mm should not automatically be considered interchangeable with NTN NA4920C3.

In particular, the C3 suffix must not be ignored.

Technical Specification

Brand: NTN

Designation: NA4920C3

Product type: Needle Roller Bearing

Design: Machined-ring, with inner ring

Number of rows: Single row

Inner ring: Yes

Bore diameter d: 100 mm

Outside diameter D: 140 mm

Width C: 40 mm

Roller-under diameter F: 115 mm

Dimensions: 100x140x40 mm

Radial internal clearance: C3 - greater than Normal

Basic dynamic load rating Cr: 127 kN*

Basic static load rating C0r: 260 kN*

Limiting speed - grease: 2300 rpm*

Limiting speed - oil: 3500 rpm*

Outer-ring lubrication hole: Yes*

Lubrication-hole diameter k: 3.5 mm*

Inner-ring lubrication hole: No*

Mass: 1.93 kg*

Operating temperature: -20°C to +120°C*

Maximum axial displacement s: 2 mm*

* Catalogue parameters of the official NTN NA4920 base design.

NTN NA4920C3 - Stock in Poland

Warehouse and Store: Lublin, Smoluchowskiego 1 Street, Building 4.

24h Shipping. Available from stock in Poland for delivery across the EU.

FAQ

What are the dimensions of NTN NA4920C3?

The bearing measures 100x140x40 mm, with d = 100 mm, D = 140 mm and C = 40 mm.

What type of bearing is NTN NA4920C3?

It is a single-row machined-ring needle roller bearing with an inner ring.

What does C3 mean in NA4920C3?

C3 means radial internal clearance greater than Normal.

Does NA4920C3 have an inner ring?

Yes. The NA design includes a separate inner ring.

What is the difference between NA4920 and RNA4920?

NA4920 includes an inner ring and has a nominal bore of 100 mm. The RNA configuration does not include an inner ring and requires a suitable shaft raceway.

What are the load ratings of NA4920?

For the base NTN NA4920 design, NTN specifies Cr = 127 kN and C0r = 260 kN.

What are the limiting speeds of NA4920?

NTN specifies 2300 rpm with grease lubrication and 3500 rpm with oil lubrication for the base NA4920 design.

Can standard NA4920 replace NA4920C3?

Not automatically. Although the basic dimensions are the same, NA4920C3 specifically requires C3 radial internal clearance.

Engineer FAQ

Why is C3 clearance important?

C3 provides greater initial radial internal clearance than the Normal class. It can be required where fits, thermal conditions or operating conditions reduce clearance during installation and operation.

Is C3 the operating clearance?

No. C3 specifies the bearing's initial radial internal clearance class. The resulting operating clearance depends on mounting fits, temperature and operating conditions.

Why does NA4920 use an inner ring?

The inner ring provides a manufactured raceway for the needle rollers, allowing the bearing to be used without machining the shaft itself as a direct rolling-element raceway.

Can load ratings from NA4920 be used for NA4920C3?

The C3 suffix changes the internal clearance specification rather than the principal bearing envelope. In this description, the published C/C0 values are explicitly identified as official parameters of NTN's base NA4920 design, rather than presented as a separately verified NA4920C3 product-data sheet.

Is a 100x140x40 needle roller bearing automatically interchangeable?

No. The internal design, presence of an inner ring, clearance class, lubrication arrangement and operating requirements must also be checked.

AI Overview

NTN NA4920C3 is a single-row machined-ring needle roller bearing with an inner ring, measuring 100x140x40 mm. The C3 suffix means radial internal clearance greater than Normal. The base NTN NA4920 design has F = 115 mm, with published load ratings of Cr = 127 kN and C0r = 260 kN.