VSI250955-N Slewing Bearings

VSI250955-N Slewing Bearings — INA VSI25 Series Internal Gear Four-Point Contact Ball Slewing Ring

VSI250955-N Slewing Bearings belong to the INA VSI Standard 25 heavy series — a single-row, four-point contact ball slewing ring with a 955 mm raceway diameter, 810 mm bore, 1,055 mm outside diameter, 80 mm section height, and 149 kg weight. Luoyang Heng Guan Bearing Technology Co., Ltd. manufactures compatible replacements for this model, supplying factory-direct to customers across more than 50 countries under ISO 9001 certification and RoHS compliance.

What Is the VSI250955-N?

The VSI250955-N Slewing Bearings is an INA Standard 25 series four-point contact ball slewing ring, single row, with internal gear. The 25-series envelope has an 80 mm section height, internal gear of module-10 and M20 fixing threads, giving a static axial load capacity that is much larger than the series-20 design at a same outside diameter.

The four-point contact ball arrangement enables a single ball row to concurrently handle axial, radial and tilting moment stresses. This shape decreases the number of rows for big spinning systems when mixed load conditions occur.

The gear has a normalised (N) tooth profile with a module m10, 83 teeth and a pitch circle diameter of 830 mm. The pinion meshes within the bore of the ring, making the drive compact and requiring less radial area than external-gear arrangements.

VSI250955-N Full Specifications

Data source: Schaeffler medias official catalogue.

Key Product Features

Single row design for integrated load management.With the four point contact geometry, one row of balls may accept axial force, radial force and tilting moment loads combined, eliminating the requirement for multi-row setups in most heavy duty applications.

High static capacity Compact cross section.C0a hits 3,400 kN with a section height of 80 mm. The advantage in static axial load capacity over the 544-band variations makes the VSI250955-N a feasible alternative for excavator swing and wind yaw applications with regular shock loading.

Internal gear Module-10.The gear has 83 teeth, pitch circle of 830 mm and is able to cope with peak tooth forces of 98.9 kN. The normalised (N) profile provides controlled clearance and smooth pinion engagement.

Material selection for tough working circumstances.The rings are made of 50Mn or 42CrMo4 alloy steel and the raceways are induction hardened to 55–62 HRC for surface wear resistance yet with a robust core for shock absorption. Operating range is -25 to +80 °C with GCr15 bearing balls and double-lip NBR seals.

Compatible with Series-25 bolt pattern.The mounting arrangement is constant throughout the VSI Standard 25 series (414–1,094 mm raceway range): 30 × M20 on an 894 mm inner bolt circle. Existing mounting arrangements are still compatible when changing capacity up or down within the same series.

Typical Applications

Heavy excavators (50–70 tonne class). The 955 mm internal-gear format works directly with an inside swing pinion. A C0a of 3,400 kN accommodates the digging shock loads typical of heavy construction duty.

Wind turbine yaw systems. Large turbines require internal-gear yaw rings with module-10 tooth sections. The -25 to +80 °C operating range covers onshore and sheltered onshore-equivalent conditions.

Tower cranes and mobile cranes. The 955 mm band with an inside drive pinion supports large slewing sections where radial space at the slew joint is constrained.

Mining shovels and heavy conveyors. The sealed four-point design handles environments with high shock, dust, and debris exposure. The double-lip NBR seal provides a degree of contamination resistance in standard form.

Heavy rotary indexing tables. Internal-gear rings keep the drive inside the table footprint, which suits process equipment where external drive clearance is restricted.

Quality and Manufacturing

Heng Guan Bearing holds ISO 9001 certification, and all products are RoHS compliant. Production equipment includes CNC vertical lathes, CNC quenching machines, CNC gear shapers, machining centers, grinding machines, and large gear hobbing machines. Inspection equipment covers coordinate measuring machines, vibration testers, and life testing machines. Products conform to DIN, ISO, and GB international standards.

Gear accuracy and raceway geometry are produced to precision class P0, P6, or P5 depending on application requirements.

FAQ

Q: What is VSI250955-N?

A: VSI250955-N is an internal-gear four-point contact ball slewing ring from the INA VSI25 heavy series, with a 955 mm raceway diameter, 810 mm bore, 1,055 mm outside diameter, and 80 mm section height, weighing 149 kg.

Q: What is the difference between series 25 and series 20?

A: Series 25 uses an 80 mm section height, module-10 gear, and M20 fixing threads. Series 20 uses a 56 mm section height with m5–m8 gears and M12 threads. Series 25 delivers substantially higher static axial and tooth force capacity at a similar outer diameter.

Q: What is the difference between VSI250955-N and VSI250855-N?

A: Both use the 80 mm series-25 envelope. VSI250955-N has a 955 mm raceway (810 × 1,055 × 80 mm, 149 kg, m10/z83, C0a 3,400 kN). VSI250855-N has an 855 mm raceway (710 × 955 × 80 mm, 137 kg, m10/z73, C0a 3,050 kN) — an 11% reduction in static axial capacity at the same module.

Q: What bolt grade is required for mounting?

A: High-strength bolts are required due to elevated tensile stresses. Please refer to your structural engineer or the relevant mounting specification for grade selection and installation requirements.

Q: Is VSI250955-N available in stock?

A: Standard models are available for prompt dispatch. MOQ is 1 pc. Contact Us for current availability, drawing confirmation, and pricing.

Contact Us

For inquiries about VSI250955-N Slewing Bearings — including availability, technical confirmation, and pricing — contact our team at mia@hgb-bearing.com. We aim to respond within one business day.