VSI200944-N Slewing Bearings

VSI200944-N Slewing Bearings — INA VSI Standard 20 Internal Gear Four-Point Contact Ball Slewing Ring

VSI200944-N Slewing Bearings belong to the INA VSI Standard 20 series — a single-row, four-point contact ball design with an internal gear (m8/z107), a 944 mm raceway diameter, and a static axial load capacity of 1,520 kN. Luoyang Heng Guan Bearing Technology Co., Ltd. manufactures and supplies this model to industries including wind energy, crane engineering, and heavy-duty industrial rotation, with ISO 9001 certification and RoHS compliance covering the production process.

What Is the VSI200944-N?

The VSI200944-N is part of INA's VSI Standard 20 slewing ring family. Its single-row, four-point contact ball structure allows one ball row to simultaneously carry axial forces, radial forces, and tilting moment loads — keeping the assembly compact without requiring multiple bearing rows.

The internal gear places the pinion inside the ring bore, which shields the gear mesh from external debris and reduces the radial footprint of the drive system. This geometry is well suited to wind turbine nacelles and excavator swing housings where space is constrained.

The "N" suffix designates normalized gear teeth on the bearing ring — it describes the heat-treatment condition of the tooth zone, not a tooth-profile class. Tooth geometry is defined by the gear data (m 8, z 107, d0 856 mm), while clearance is governed by the clearance or preload variant ordered (RL0/RL1/RL2 reduced clearance, VSP preload).

Full Technical Specifications

Source: Schaeffler medias official catalogue

Key Technical Characteristics

Four-point contact ball design. A single ball row handles combined axial, radial, and tilting moment loads simultaneously. This eliminates the need for additional bearing rows and keeps section height at 56 mm.

Static axial capacity. At C0a = 1,520 kN, the VSI200944-N carries a +12% static axial load compared to the 844 mm band (C0a = 1,360 kN) at the same module 8 gear specification and identical section height.

Normalized internal gear teeth. The m8/z107 internal gear is supplied with normalized teeth on the bearing ring. Permissible tooth force is 31.4 kN at tooth-root fatigue strength (shock factor 1.2) and 46.7 kN at tooth-root fracture strength (shock factor 1.35). Pinion meshing occurs inside the bore, forming a compact and enclosed drive envelope.

Ring and ball materials. Rings use 50Mn or 42CrMo4 steel with induction-hardened raceways (55–62 HRC surface hardness). Balls use GCr15 bearing steel. Double-lip NBR seals support grease retention across the -25°C to +80°C operating range.

Mounting interface. Fixing is by 44 through-holes (dB 14 mm) on a 990 mm bolt circle in the outer ring, and 44 M12 threaded holes, 20 mm deep, on a 905 mm bolt circle in the inner ring. Bearings carrying the same designation can be exchanged across tooth-condition and clearance variants (RL0/RL1/RL2 reduced clearance, VSP preload) without altering the mounting structure. Moving to another size in the VSI 20 series — for example VSI200844-N, with La 890/40 holes and Li 805/40 holes — requires re-checking bolt circles, centering diameters and pinion centre distance.

Application Areas

The VSI200944-N Slewing Bearings is used in applications requiring large-diameter rotation, high static load capacity, and internal-gear drive integration:

· Wind Turbine Yaw Systems — The internal-gear design and m8 tooth section provide larger yaw driving torques across the complete operating temperature range. The static margin of C0a 1,520 kN is enough to absorb different wind loads over long periods of operation.

· Tower Cranes & Mobile Cranes – The 844 mm band is load restricted in big crane slewing sections. The m8/z107 internal gear and 1,520 kN static axial capacity cover the driving torque requirements.

· Excavator Upperstructure Rotation — The 840 mm bore for big rotary unions. The static margin C0a 1,520 kN can take digging shock loads in the 50-tonne class.

· Solar Tracker Drive Heads - The 944 mm raceway can accommodate big tracker drive assemblies with internal pinion drives in terms of tilt-moment capacity.

· Radar & Antenna Platforms – The normalised internal gear facilitates clearance-controlled tracking rotation of large radar and satellite antenna systems.

· Rotary Indexing Tables – Large diameter rotary indexers use the internal drive geometry, which retains the drive mechanism inside the table footprint. VSP preloaded and RL reduced-clearance available on request.

· Offshore & Marine Deck Equipment – Ideal for salt-spray situations, due to NBR-sealed construction. Please validate surface treatment choices at inquiry for unique corrosion protection needs.

Manufacturing and Quality

Heng Guan Bearing produces slewing bearings ranging from 50 mm to 10,000 mm in diameter, with precision grades P0, P6, P5, and P4. Production equipment for this model includes CNC vertical lathes, CNC quenching machines, CNC gear shapers, grinding machines, and large gear hobbing machines.

Quality control uses coordinate measuring machines, vibration testers, and life testing machines. Each bearing is traceable from raw material to finished product. The company holds ISO 9001 certification, and products comply with DIN, ISO, and GB standards, with RoHS compliance.

Engineering support includes technical consultation, installation guidance, and OEM/ODM partnerships. For specific lead times, stock availability, and minimum order quantities, please Contact Us directly.

FAQ

Q: What is the confirmed outside diameter of the VSI200944-N?

A: 1,016 mm (tolerance 0 / -0.7 mm). The bore is 840 mm, overall height 56 mm. The outer ring carries 44 through-holes of 14 mm on a 990 mm bolt circle; the inner ring carries 44 M12 threaded holes, 20 mm deep, on a 905 mm bolt circle.

Q: What are the gear specifications?

A: Internal gear, module 8, 107 teeth, pitch circle diameter 856 mm, normalized (N) profile. Continuous tooth force rating is 31.4 kN; peak tooth force rating is 46.7 kN, per Schaeffler medias catalogue data.

Q: How does the VSI200944-N compare to the VSI200844-N?

A: Both use a 56 mm section height and module 8 gear. The VSI200944-N has a 944 mm raceway, 840 mm bore, 76 kg weight, 107 teeth, and C0a of 1,520 kN. The VSI200844-N has an 844 mm raceway, 736 mm bore, 69 kg weight, 94 teeth, and C0a of 1,360 kN — a difference of approximately +12% in static axial capacity at the same gear module.

Q: What clearance and precision classes are available?

A: Standard radial clearance is 0–0.3 mm; axial tilting clearance is 0–0.53 mm. Precision classes P0, P6, and P5 are available. VSP preloaded and RL reduced-clearance variants are available on request.

Q: What bolt grade is required for installation?

A: High-strength bolts of grade 10.9 or 12.9 (ISO) are required. Use bolts with an unthreaded shank in the shear plane, and position the S-mark (soft spot) in the non-load-bearing zone during installation.

Q: Is the VSI200944-N suitable for sub-zero environments?

A: The standard operating range is -25°C to +80°C. For environments below -20°C, verify grease selection — low-temperature synthetic grease is recommended to maintain lubrication film integrity.

Contact Us

For pricing, availability, or technical documentation for VSI200944-N Slewing Bearings, reach our engineering team at mia@hgb-bearing.com. We respond to all inquiries.