K 58X65X18 H KOYO 58x65x18 Needle Roller and Cage Assembly

What Is K 58X65X18 H KOYO?

K 58X65X18 H KOYO is a radial needle roller and cage assembly with dimensions 58x65x18 mm, belonging to the metric K series. The component consists of needle rollers retained and guided by a cage. It is not a complete bearing with integral inner and outer rings. In a correctly designed bearing arrangement, the shaft and housing surfaces act directly as raceways for the needle rollers. This construction provides high radial load capacity within a very small radial installation space.

Compact Design Without Integral Bearing Rings

The defining feature of KOYO K58X65X18H is its needle roller and cage assembly design. Instead of using a complete bearing with separate inner and outer rings, the assembly consists primarily of needle rollers and their supporting cage.

The catalog dimensions are Fw 58 mm, Ew 65 mm and Bc 18 mm. The small difference between Fw and Ew enables a particularly compact radial cross-section.

Because there are no integral bearing rings, the dimensions and condition of the shaft and housing surfaces are important elements of the complete bearing arrangement.

Radial Load Capacity and Speed

KOYO specifies a basic dynamic load rating Cr of 34.3 kN and a basic static load rating C0r of 67.1 kN for K58X65X18H. The fatigue load limit Cu is 10.7 kN.

The limiting speed depends on lubrication. The manufacturer specifies 4700 rpm with grease lubrication and 7300 rpm with oil lubrication.

These values should be considered together with the actual radial load, lubrication conditions and design of the complete bearing arrangement.

Technical Specification

Manufacturer: KOYO / JTEKT

Type: Radial needle roller and cage assembly

Part Number: K58X65X18H

Series: Metric K series

Fw: 58 mm

Ew: 65 mm

Bc: 18 mm

Cage material designation: S

Basic Dynamic Load Rating Cr: 34.3 kN

Basic Static Load Rating C0r: 67.1 kN

Fatigue Load Limit Cu: 10.7 kN

Limiting Speed with Grease Lubrication: 4700 rpm

Limiting Speed with Oil Lubrication: 7300 rpm

Recommended Shaft Dimension S: 57.987 to 58.000 mm

Recommended Housing Dimension H: 65.010 to 65.029 mm

Mass: Approximately 0.058 kg

Why the Ringless Construction Matters

In the K58X65X18H needle roller assembly, the rolling elements operate directly against appropriately prepared surfaces of the surrounding machine components. Eliminating integral bearing rings reduces the radial space required for the bearing arrangement.

This design principle also means that K58X65X18H should not be treated as a direct replacement for any complete needle roller bearing with similar dimensions. The surrounding bearing seat must be designed for a needle roller and cage assembly.

How to Select K 58X65X18 H KOYO

Selecting K 58X65X18 H KOYO requires more than matching the nominal 58x65x18 mm dimensions.

The selection process should verify:

• Exact K58X65X18H designation
• Design of the existing bearing arrangement
• Shaft dimensions and raceway condition
• Housing dimensions and raceway condition
• Required radial load capacity
• Operating speed
• Lubrication method
• Actual operating conditions
• Requirements for surfaces acting as needle roller raceways

KOYO specifies recommended dimensional ranges for the mating shaft and housing. These should be considered together with the technical documentation of the machine or assembly.

Lubrication and Operating Speed

Lubrication directly influences the limiting speed specified for this model. KOYO lists a limiting speed of 4700 rpm with grease and 7300 rpm with oil.

The appropriate lubricant and lubrication method should therefore be selected according to the complete bearing arrangement, operating speed and actual service conditions rather than the cage assembly alone.

Why Engineers Choose K58X65X18H

• Ringless construction minimizes radial installation space.
• Fw 58 mm provides precise identification of the required assembly size.
• Ew is 65 mm with a compact Bc width of 18 mm.
• Basic dynamic load rating reaches 34.3 kN.
• Basic static load rating reaches 67.1 kN.
• Needle roller construction provides substantial radial load capacity relative to its cross-section.
• KOYO specifies recommended shaft and housing dimensions for the assembly.
• Separate limiting speeds are specified for grease and oil lubrication.

Maintenance, MRO and Machine Repair

For maintenance and MRO operations, KOYO K58X65X18H should be identified using the complete manufacturer designation together with the Fw, Ew and Bc dimensions.

This is particularly important during machine repair because visually similar needle roller cage assemblies can differ in width, diameter, load ratings or requirements for mating raceway surfaces.

Correct identification helps maintenance departments avoid installing a dimensionally similar component with different catalog characteristics.

FAQ

Is K 58X65X18 H KOYO a complete needle roller bearing?

No. K58X65X18H is a radial needle roller and cage assembly. It does not incorporate conventional inner and outer bearing rings.

What do the 58x65x18 dimensions mean?

According to KOYO catalog data, Fw is 58 mm, Ew is 65 mm and the cage assembly width Bc is 18 mm.

Can K58X65X18H be called a needle roller cage?

Yes. "Needle roller cage" is commonly used commercially for this type of component. The more precise manufacturer classification is radial needle roller and cage assembly.

What is the load capacity of K58X65X18H?

KOYO specifies a basic dynamic load rating Cr of 34.3 kN and a basic static load rating C0r of 67.1 kN.

What shaft dimension is recommended?

The manufacturer specifies a recommended shaft dimension S of 57.987 to 58.000 mm.

What housing dimension is recommended?

KOYO specifies a recommended housing dimension H of 65.010 to 65.029 mm.

What is the limiting speed of K58X65X18H?

The specified limiting speed is 4700 rpm with grease lubrication and 7300 rpm with oil lubrication.

Can I select an equivalent only by the 58x65x18 dimensions?

No. The complete designation, construction, load ratings, speed, lubrication and requirements for the mating shaft and housing surfaces should also be verified.