Guide rail roller bearings (also called track roller bearings or cam followers) are the core rolling elements of linear motion systems. Ningbo Shuanghua Bearing (NLHB) manufactures both the SG series and the VW series guide rail roller bearings. This article explains the structural and performance differences between the two lines and how to select the correct series for your application.
Overview: SG Series vs. VW Series Guide Rail Roller Bearings
Both series run on linear guide rails, but they are engineered for different working conditions. The SG series is built for high-precision, high-load linear guidance on CNC machine tools and measuring equipment, while the VW series is a cost-effective, impact-resistant solution for material handling and conveyor applications where moderate precision is acceptable.
Key Features of the SG Series Guide Rail Roller Bearing
- Gothic-arch groove with a 45° contact angle for stable two-point contact.
- High load capacity, capable of carrying heavy radial and axial loads.
- High precision, manufactured to P4 / P2 tolerance grades.
- Sealed design with dust- and leak-proof seals for long service life.
Key Features of the VW Series Guide Roller Bearing
- V-groove design matched to the profile of the guide rail.
- Double-row construction for high rigidity under shock loads.
- Wide operating temperature range: -30°C to +120°C.
- Impact resistance, suited for heavy, intermittent duty.
Technical Specifications
Common SG series part numbers and reference dimensions (bore × outer diameter × width, in mm):
| Part No. | Bore (mm) | Outer Diameter (mm) | Width (mm) |
|---|---|---|---|
| SG15 | 5 | 17 | 8 |
| SG20 | 6 | 24 | 11 |
| SG25 | 8 | 30 | 14 |
Notes: Dimensions above are reference values for the listed SG series part numbers. Full dimension tables, dynamic/static load ratings and limit speeds for each size are available on request. NLHB also supplies the corresponding VW series guide rollers; please specify the rail profile and required load when requesting a quote.
Selection Guide: How to Choose Between SG and VW
Choose the SG series when your application requires:
- High-precision linear motion;
- Heavy, continuous loading;
- CNC machine tool or precision measuring service;
- Long, maintenance-free service life.
Choose the VW series when your application involves:
- Material handling and conveyor transport;
- Cost-sensitive projects;
- Moderate precision requirements;
- Intermittent or shock-loaded duty.
Typical Applications
SG series is widely used in CNC machine tool guide systems, automation equipment, industrial robots and precision measuring instruments.
VW series is widely used in logistics conveyor systems, automated assembly lines, material handling equipment and warehouse / storage systems.
Cross-Reference and Interchangeability
SG and VW guide rail roller bearings follow the standard track-roller form factor and are dimensionally interchangeable with equivalent sizes from major global brands. When replacing an installed unit, cross-reference by bore diameter, outer diameter, outside profile (gothic-arch vs. V-groove) and track roller type rather than by trade name alone. Suitable global references include the corresponding track roller / cam follower series from SKF, INA, NSK, NTN, FAG and Timken. For an exact cross-reference against your current part number, provide NLHB with the stamped code and rail profile and we will confirm the matching SG or VW equivalent.
Why Choose Ningbo Shuanghua Bearing (NLHB)
- ~30 years of bearing manufacturing experience.
- Precision production equipment ensuring consistent tolerances.
- Non-standard / custom sizes supported.
- Fast 7-day delivery on standard items.
Contact us for a quote: Hu Jianghua – +86 188-5801-2678
FAQ
1. What is the main difference between the SG and VW series?
The SG series uses a gothic-arch groove (45° contact angle) for high precision and heavy loads on CNC and measuring equipment, while the VW series uses a V-groove, double-row design optimized for impact resistance and cost efficiency in conveyor and material handling applications.
2. What tolerance grades are available for the SG series?
The SG series is manufactured to P4 and P2 precision grades.
3. What is the operating temperature range of the VW series?
The VW series operates from -30°C to +120°C.
4. Can NLHB supply non-standard guide roller sizes?
Yes. NLHB supports custom and non-standard guide rail roller bearings; contact us with your drawing or sample requirement.