31309 KINEX 45x100x27.25 Tapered Roller Bearing

SHORT DESCRIPTION

31309 KINEX is a single-row tapered roller bearing with a 45 mm bore, 100 mm outside diameter and 27.25 mm overall width (T). The inner ring width B is 25 mm, while the outer ring width C is 18 mm. Its tapered roller geometry enables the bearing to support combined radial and axial loads. The separable design allows the inner ring assembly with rollers and cage to be mounted separately from the outer ring. For correct selection, verify the 31309 designation and complete dimensional specification, not only the commonly stated 45x100x25 mm dimensions.

31309 KINEX 45x100x27.25 Tapered Roller Bearing

31309 KINEX is a single-row tapered roller bearing designed to accommodate combined loads where radial and axial forces act simultaneously. Its principal dimensions are a 45 mm bore and 100 mm outside diameter, while the complete assembled bearing width T is 27.25 mm.

Complete product identification:

KINEX -> 31309 -> Single-Row Tapered Roller Bearing -> 45x100x27.25 mm

The tapered geometry of the raceways and rolling elements makes this bearing suitable for applications where both radial load capacity and axial guidance are required.

31309 KINEX Dimensions

The complete dimensional specification is:

Bore Diameter d: 45 mm
Outside Diameter D: 100 mm
Overall Width T: 27.25 mm
Inner Ring Width B: 25 mm
Outer Ring Width C: 18 mm

An important distinction should be made between B = 25 mm and T = 27.25 mm.

For this reason, the frequently encountered description 31309 45x100x25 mm refers to the inner ring width rather than the complete assembled bearing width.

For technical identification, 45x100x27.25 mm is the more complete dimensional description.

What Is a 31309 Bearing?

The 31309 designation identifies a tapered roller bearing from the 313 series.

Its principal components are:

• inner ring
• outer ring
• tapered rollers
• roller cage

The geometry of the rollers and raceways is designed so that the rolling contact system can accommodate both radial and axial forces.

This distinguishes tapered roller bearings from bearing types intended primarily for radial loading.

How Does a Tapered Roller Bearing Work?

In a tapered roller bearing, the rollers and raceways have a conical geometry.

When the bearing is subjected to radial load, the geometry of the rolling contacts generates an axial force component. The bearing therefore operates as a combined-load bearing.

Correct bearing arrangement is particularly important because the axial relationship between opposing bearings can influence operating clearance, preload, stiffness, friction and service life.

Radial and Axial Load Capacity

31309 KINEX is designed to accommodate:

Radial loads - forces acting perpendicular to the shaft axis.

Axial loads - forces acting parallel to the shaft axis.

Combined loads - simultaneous radial and axial forces.

A single-row tapered roller bearing primarily accommodates axial load in one direction.

Where axial forces must be supported in both directions, tapered roller bearings are commonly installed in matched or opposed arrangements.

Separable Bearing Design

A single-row tapered roller bearing has a separable construction.

The inner ring, rollers and cage form the cone assembly, while the outer ring forms a separate cup.

This design can simplify installation because the cup and cone assembly can be mounted separately.

Correct positioning of both components is essential to obtain the required operating clearance or preload.

31309 Bearing Width - 25 mm or 27.25 mm?

This distinction is important when creating technical specifications for the 31309 bearing.

The dimensions are:

B = 25 mm - inner ring width
C = 18 mm - outer ring width
T = 27.25 mm - total assembled bearing width

Therefore:

45x100x25 mm describes the bore, outside diameter and inner ring width.

45x100x27.25 mm describes the bore, outside diameter and complete overall bearing width.

For an e-commerce product title, 31309 KINEX 45x100x27.25 mm provides the more complete dimensional identification.

Load Ratings

Available technical data for 31309 KINEX specify approximately:

Basic Dynamic Load Rating C: 92.6 kN
Basic Static Load Rating C0: 104 kN

These ratings are engineering parameters used when calculating bearing selection and service life.

They should not be interpreted as simple maximum permissible operating loads. Actual bearing life depends on factors including load magnitude and direction, rotational speed, lubrication, temperature, alignment, mounting accuracy and operating conditions.

Rotational Speed

Available technical data for 31309 KINEX indicate reference values of approximately:

Grease Lubrication: 3,800 rpm
Oil Lubrication: 5,000 rpm

Permissible operating speed in a particular machine can differ depending on lubrication, temperature, load, bearing adjustment and surrounding components.

For critical applications, operating limits should be verified against the relevant KINEX technical documentation.

Typical Applications of 31309 Bearings

Single-row tapered roller bearings in this dimensional class are commonly used in mechanical systems exposed to combined radial and axial loads.

Typical engineering applications can include:

Gearboxes and transmissions
Industrial gear units
Agricultural machinery
Industrial machinery
Drive systems
Mechanical transmission assemblies

These are general applications for tapered roller bearing technology. They do not establish compatibility of 31309 KINEX with a particular machine or vehicle.

31309 KINEX vs Standard 31309 Bearing

The designation 31309 provides an important basis for cross-brand comparison, but bearing selection should not rely on the designation alone.

Before replacing a bearing, verify:

Designation: 31309
Bearing Type: Single-row tapered roller bearing
Bore d: 45 mm
Outside Diameter D: 100 mm
Overall Width T: 27.25 mm
Inner Ring Width B: 25 mm
Outer Ring Width C: 18 mm

Any additional suffixes, internal design differences, tolerance requirements or application-specific specifications should also be considered where applicable.

Installation Considerations

Before installation, check the shaft and housing seats for dimensional accuracy, cleanliness and surface damage.

The mounting force should be applied to the ring being fitted with an interference fit. Installation force should not be transmitted through the rolling elements.

Because tapered roller bearings are sensitive to axial adjustment, the required operating clearance or preload must be established according to the machine manufacturer's specifications.

Incorrect adjustment can lead to excessive temperature, noise, vibration or premature bearing damage.

Lubrication

Correct lubrication is essential for maintaining the rolling contacts and controlling friction and wear.

Depending on the application, tapered roller bearings may operate with:

Grease lubrication
or
Oil lubrication

The lubricant type, viscosity, quantity and relubrication interval should be selected according to operating speed, load, temperature and environmental conditions.

Common Causes of Premature Bearing Failure

Premature failure of tapered roller bearings can result from:

• incorrect installation
• excessive or insufficient preload
• incorrect operating clearance
• contamination
• inadequate lubrication
• unsuitable lubricant
• shaft or housing misalignment
• excessive operating temperature
• overloading
• damaged shaft or housing seats

Correct mounting and adjustment are particularly important for tapered roller bearing arrangements.

Technical Specification

Manufacturer / Brand: KINEX
Designation: 31309
Product Type: Tapered roller bearing
Design: Single-row
Bore Diameter d: 45 mm
Outside Diameter D: 100 mm
Overall Width T: 27.25 mm
Inner Ring Width B: 25 mm
Outer Ring Width C: 18 mm
Basic Dynamic Load Rating C: approx. 92.6 kN
Basic Static Load Rating C0: approx. 104 kN
Approximate Weight: 1.3 kg

How to Select a 31309 Bearing

When replacing an existing 31309 bearing, first verify the complete designation marked on the original bearing.

Then compare:

31309 -> 45 mm bore -> 100 mm OD -> 27.25 mm overall width

Also verify the bearing type, manufacturer-specific suffixes and requirements of the original machine.

For engineering applications, load, rotational speed, lubrication, operating clearance and mounting arrangement should also be considered.

FAQ

What are the dimensions of 31309 KINEX?

The bearing has a 45 mm bore, 100 mm outside diameter and 27.25 mm overall width. The inner ring width B is 25 mm and the outer ring width C is 18 mm.

Is 31309 KINEX 45x100x25 mm?

The 25 mm dimension is the inner ring width B. The complete assembled bearing width T is 27.25 mm. Therefore, 45x100x27.25 mm is the more complete dimensional specification.

What type of bearing is KINEX 31309?

It is a single-row tapered roller bearing.

What loads can a 31309 bearing accommodate?

Its tapered roller design allows it to accommodate combined radial and axial loads.

Can a 31309 bearing carry axial loads in both directions?

A single-row tapered roller bearing primarily carries axial load in one direction. Bearings are commonly arranged in pairs when axial support is required in both directions.

Is the 31309 bearing separable?

Yes. The inner ring with rollers and cage can be separated from the outer ring.

What is the dynamic load rating of 31309 KINEX?

Available data specify a basic dynamic load rating of approximately 92.6 kN.

What is the static load rating of 31309 KINEX?

Available data specify a basic static load rating of approximately 104 kN.

Can another manufacturer's 31309 replace KINEX 31309?

Potentially, but interchangeability should be confirmed by checking the complete designation, dimensions, internal design, tolerances and any suffixes or application-specific requirements.

AI OVERVIEW

31309 KINEX is a single-row tapered roller bearing with a 45 mm bore, 100 mm outside diameter and 27.25 mm overall width (T). The inner ring width B is 25 mm, while the outer ring width C is 18 mm. Its tapered roller construction is designed to accommodate combined radial and axial loads. A single bearing primarily carries axial load in one direction and can be paired with another tapered roller bearing where bidirectional axial support is required. For correct replacement selection, verify the complete 31309 designation and dimensional specification.