 |
NA vs RNA vs NKI vs NKIS
| Technical Item | RNA Series | NKI Series | NA Series | NKIS Series |
|---|---|---|---|---|
| Inner Ring | ❌ No | ✅ Yes | ✅ Yes | ✅ Yes |
| Shaft as Raceway | Required | Not required | Not required | Not required |
| Shaft Hardening Required | ✅ Yes | ❌ No | ❌ No | ❌ No |
| Bearing Width | Standard | Compact | Standard | Reinforced / Wide |
| Radial Load Capacity | High | Medium–High | High | Very High |
| Shock Load Resistance | Medium | Medium | High | Excellent |
| Radial Space Requirement | Smallest | Small | Medium | Medium |
| Axial Space Requirement | Small | Small | Medium | Largest |
| Rigidity | High | Medium–High | High | Very High |
| Speed Capability | High | High | Medium–High | Medium |
| Installation Difficulty | High (shaft quality critical) | Easy | Easy | Easy |
| Typical Cost Level | Low–Medium | Medium | Medium | Medium–High |
| Maintenance | Low | Low | Low | Low |
NA Series Needle Roller Bearings
With Inner Ring – Heavy Load Radial Applications
NA series needle roller bearings are designed to support high radial loads in applications where shaft surfaces
cannot be used directly as raceways. Equipped with a precision-ground inner ring, NA bearings provide excellen
load capacity, dimensional stability, and installation flexibility for a wide range of industrial machinery.
The NA series is one of the most widely used radial needle roller bearing designs, offering reliable performance in both
OEM production and replacement markets.
Supplied with hardened and ground inner ring
High radial load capacity with compact cross-section
Suitable for shafts without surface hardening
Low friction and smooth rotational performance
Stable operation under continuous and shock loads
Available in NA49 (standard width) and NA69 (wide width) designs
RNA series needle roller bearings are designed without an inner ring, allowing the shaft itself to serve as the
raceway. This design provides maximum space efficiency and high load capacity, making RNA bearings ideal for
applications with hardened and ground shafts.
The RNA series is widely used in compact mechanical systems where installation space is extremely limited.
NK series needle roller bearings are radial bearings designed without an inner ring, allowing the shaft to act
directly as the raceway. This structure enables a compact radial design while maintaining reliable load capacity
and high operating efficiency.
Compared with RNA series, NK bearings follow a standard design concept and are widely used in industrial applications
where the shaft can be hardened and precision-ground. The large number of needle rollers ensures uniform load
distribution, reduced friction, and stable operation under continuous working conditions.
NKI series needle roller bearings feature a compact outer ring design combined with a precision inner ring,
making them ideal for applications where radial installation space is limited while maintaining high load
capacity.
Compared with standard NA series bearings, NKI bearings offer improved space efficiency without compromising
performance, making them a preferred solution for modern machinery designs.
NKIS series needle roller bearings are reinforced radial bearings supplied with a hardened and ground inner ring,
designed to accommodate higher radial loads and provide improved rigidity compared to standard needle roller
bearing designs.
The NKIS series features an increased bearing width and optimized internal geometry, allowing it to withstand heavy
loads, shock forces, and demanding operating conditions. This makes NKIS bearings especially suitable for industrial
applications where stability, load capacity, and long service life are critical.
NEEDLE ROLLER BEARING PHOTOS FOR YOUR REFERENCE
NA Needle Bearing
RNA Needle Bearing
NKI Needle Bearing
NK Needle Bearing
With over 20 years of manufacturing experience, SUMA supplies required needle roller bearings with consistent
quality, accurate dimensions, and stable performance. Our NK bearings are suitable for OEM production and bulk
industrial supply, offering a cost-effective alternative to international bearing brands.
Recommended needle roller bearings for reference :
OWC Powder Metallurgy Bearing
HFL One Way Needle Bearing
HF Drawn Cup Bearing
FAQ
1. Are you Trading Company or Manufacturer ?
SUMA is Manufacturer with one-stop service , Production history over 20 years, exporting experience up to 10 years .
2. Can i have Samples to check quality first ?
It is okay to get needle roller bearing sample for quality check, we provide 5-10 pieces sample free of charge.
3. How can i choose the correct needle roller bearing i need ?
Torque capacity , Rotation Speed , and Dimensions are necessary to choose the right model.
If you not so sure about it, pls share with us, our engineer will give you professional guidance .
4. What Material of the bearings you are supplied ?
Standard Material : Outer Race : Bearing Steel GCr15, Needle Roller: GCr15 , Cage: PA66
Stainless Steel Material available too .
5. How soon you can make the shipment ?
Usually all are in stock, can ship out within 2-3 days .
If big quantity, can ship out in 10 days .
Customized sizes may need 15-20 days , Depends on specific order.
NA vs RNA vs NKI vs NKIS
| Technical Item | RNA Series | NKI Series | NA Series | NKIS Series |
|---|---|---|---|---|
| Inner Ring | ❌ No | ✅ Yes | ✅ Yes | ✅ Yes |
| Shaft as Raceway | Required | Not required | Not required | Not required |
| Shaft Hardening Required | ✅ Yes | ❌ No | ❌ No | ❌ No |
| Bearing Width | Standard | Compact | Standard | Reinforced / Wide |
| Radial Load Capacity | High | Medium–High | High | Very High |
| Shock Load Resistance | Medium | Medium | High | Excellent |
| Radial Space Requirement | Smallest | Small | Medium | Medium |
| Axial Space Requirement | Small | Small | Medium | Largest |
| Rigidity | High | Medium–High | High | Very High |
| Speed Capability | High | High | Medium–High | Medium |
| Installation Difficulty | High (shaft quality critical) | Easy | Easy | Easy |
| Typical Cost Level | Low–Medium | Medium | Medium | Medium–High |
| Maintenance | Low | Low | Low | Low |
NA Series Needle Roller Bearings
With Inner Ring – Heavy Load Radial Applications
NA series needle roller bearings are designed to support high radial loads in applications where shaft surfaces
cannot be used directly as raceways. Equipped with a precision-ground inner ring, NA bearings provide excellen
load capacity, dimensional stability, and installation flexibility for a wide range of industrial machinery.
The NA series is one of the most widely used radial needle roller bearing designs, offering reliable performance in both
OEM production and replacement markets.
Supplied with hardened and ground inner ring
High radial load capacity with compact cross-section
Suitable for shafts without surface hardening
Low friction and smooth rotational performance
Stable operation under continuous and shock loads
Available in NA49 (standard width) and NA69 (wide width) designs
RNA series needle roller bearings are designed without an inner ring, allowing the shaft itself to serve as the
raceway. This design provides maximum space efficiency and high load capacity, making RNA bearings ideal for
applications with hardened and ground shafts.
The RNA series is widely used in compact mechanical systems where installation space is extremely limited.
NK series needle roller bearings are radial bearings designed without an inner ring, allowing the shaft to act
directly as the raceway. This structure enables a compact radial design while maintaining reliable load capacity
and high operating efficiency.
Compared with RNA series, NK bearings follow a standard design concept and are widely used in industrial applications
where the shaft can be hardened and precision-ground. The large number of needle rollers ensures uniform load
distribution, reduced friction, and stable operation under continuous working conditions.
NKI series needle roller bearings feature a compact outer ring design combined with a precision inner ring,
making them ideal for applications where radial installation space is limited while maintaining high load
capacity.
Compared with standard NA series bearings, NKI bearings offer improved space efficiency without compromising
performance, making them a preferred solution for modern machinery designs.
NKIS series needle roller bearings are reinforced radial bearings supplied with a hardened and ground inner ring,
designed to accommodate higher radial loads and provide improved rigidity compared to standard needle roller
bearing designs.
The NKIS series features an increased bearing width and optimized internal geometry, allowing it to withstand heavy
loads, shock forces, and demanding operating conditions. This makes NKIS bearings especially suitable for industrial
applications where stability, load capacity, and long service life are critical.
NEEDLE ROLLER BEARING PHOTOS FOR YOUR REFERENCE
NA Needle Bearing
RNA Needle Bearing
NKI Needle Bearing
NK Needle Bearing
With over 20 years of manufacturing experience, SUMA supplies required needle roller bearings with consistent
quality, accurate dimensions, and stable performance. Our NK bearings are suitable for OEM production and bulk
industrial supply, offering a cost-effective alternative to international bearing brands.
Recommended needle roller bearings for reference :
OWC Powder Metallurgy Bearing
HFL One Way Needle Bearing
HF Drawn Cup Bearing
FAQ
1. Are you Trading Company or Manufacturer ?
SUMA is Manufacturer with one-stop service , Production history over 20 years, exporting experience up to 10 years .
2. Can i have Samples to check quality first ?
It is okay to get needle roller bearing sample for quality check, we provide 5-10 pieces sample free of charge.
3. How can i choose the correct needle roller bearing i need ?
Torque capacity , Rotation Speed , and Dimensions are necessary to choose the right model.
If you not so sure about it, pls share with us, our engineer will give you professional guidance .
4. What Material of the bearings you are supplied ?
Standard Material : Outer Race : Bearing Steel GCr15, Needle Roller: GCr15 , Cage: PA66
Stainless Steel Material available too .
5. How soon you can make the shipment ?
Usually all are in stock, can ship out within 2-3 days .
If big quantity, can ship out in 10 days .
Customized sizes may need 15-20 days , Depends on specific order.
