VSU251055 Slewing Bearings

VSU251055 Slewing Bearings — INA VSU25 Series Gearless Four-Point Contact Ball Slewing Ring

VSU251055 Slewing Bearings represent the largest gearless ring in the INA VSU Standard 25 series. Built on a single-row four-point contact ball structure, this model carries a 955 mm bore, 63 mm section height, and 128 kg weight, with a static axial load rating of 3,750 kN. Produced by Luoyang Heng Guan Bearing Technology Co., Ltd. — a Luoyang-based manufacturer with over 30 years in the bearing industry — these rings are ISO 9001 certified and available in precision classes P0, P6, and P5.

What Is the VSU251055?

The VSU251055 is a gearless slewing ring from the INA VSU Standard 25 series, positioned at the top of the gearless sub-family. Its four-point contact ball structure allows a single ball row to carry axial, radial, and tilting moment loads simultaneously, which reduces assembly complexity compared to multi-row designs.

With no integrated gear teeth on either ring, the VSU251055 is designed for external drive systems — including external pinions on a customer-machined ring, chain or belt drives, friction wheels, or motor-gearbox assemblies. This makes it suitable for machine configurations where the drive method is determined by the equipment designer rather than the bearing itself.

Ring material options are 50Mn and 42CrMo4 steel. Raceways are induction hardened to 55–62 HRC. Rolling elements use GCr15 bearing steel balls. Double-lip NBR seals protect against grease loss and contaminant ingress across an operating temperature range of -25 to +80 °C. Normal radial clearance is 0.03–0.13 mm.

The mounting interface is specific to each size: the 25 series runs 24, 28, 30 and 30 fixing holes from the 755 to the 1,055, and both pitch circles move with the diameter. A unit of the same designation is a direct dimensional replacement; moving within the series, or between the 20 and 25 series, requires the mating structure to be re-checked.

Full Specifications

Data source: Schaeffler medias official catalogue.

Design Features

Four-point contact ball structure. One ball row handles axial, radial, and tilting moment loads together, reducing the total number of components compared to multi-row alternatives.

Gearless configuration. The absence of integrated gear teeth allows the drive system to be selected independently of the bearing. External pinion, chain, friction wheel, and motor-gearbox configurations are all compatible.

Static capacity at the top of the gearless 25 series. The C0a of 3,750 kN is a measurable step up from the VSU250955 (C0a 3,400 kN) within the same 63 mm section height. This margin is relevant when the equipment must absorb peak shock loads in service.

30-hole bolt pattern on a 995 mm inner circle. The bolt layout is consistent across the VSU25 family, which simplifies replacement procedures.

42CrMo4 material option. Where shock loading is a primary concern, the quenched-and-tempered 42CrMo4 ring offers greater toughness than the standard 50Mn option.

Typical Applications

The VSU251055 Slewing Bearings is suited to slow-speed, high-load environments where static capacity and structural durability are the primary selection criteria.

· Heavy cranes and mobile cranes — The 3,750 kN static axial load rating addresses the demands of large hook load conditions within the gearless 25 series.

· Wind turbine yaw systems — Gearless rings with external pinion drives operating across the full -25 to +80 °C temperature range.

· Large excavator swing systems — High static capacity and a 30-hole mounting pattern support demanding digging-cycle shock loads.

· Mining shovels, crushers, and conveyors — Four-point contact ball structure handles combined loads under sealed conditions.

· Heavy rotary indexing tables — Chain or friction-wheel driven configurations with large-diameter mounting frames.

· Offshore and deck equipment — The 3,750 kN static capacity and available material options are relevant for marine environments.

· Hydropower gate hoists and ship lifts — High static capacity at very slow rotation rates.

About Heng Guan Bearing

Luoyang Heng Guan Bearing Technology Co.,Ltd. manufactures slewing bearings of sizes from 50 mm to 10,000 mm, precision grade P0, P6, P5, P4. Production Equipment: CNC Vertical Lathe CNC Quenching Machine CNC Gear Shaper Machining Center Grinding Machine Big Gear Hobbing Machine

Quality Control, coordinate measuring equipment, vibration testers and life testing devices provide total traceability from source material to finished product.

OEM and ODM orders are accepted MOQ is 1 item. Standard stock models ship within 2 to 3 days. Services: technical consultation, product design support, installation instruction, reference part mapping, non-standard customisation. Products sent to the United States, Germany, United Kingdom, Italy, Turkey, Russia, Norway, Australia, Malaysia, South Africa and over 50 other countries.

FAQ

Q: What is the VSU251055?

A: The VSU251055 is a gearless four-point contact ball slewing ring from the INA VSU Standard 25 series — the largest gearless ring in this family. It has a 955 mm bore, 63 mm height, 128 kg weight, and a static axial load rating of 3,750 kN.

Q: What are the key dimensions?

A: Bore 955 mm, outside diameter 1,155 mm, height 63 mm, weight 128 kg. Outer bolt circle 1,115 mm with 30 fixing holes; inner bolt circle 995 mm with 30 holes; fixing bore 22 mm. Section width 54 mm. Axial tilting clearance 0.05–0.24 mm at standard radial clearance 0.03–0.13 mm.

Q: How does the VSU251055 compare to the VSU250955?

A: Both share the same 63 mm section height within the series-25 envelope. The VSU251055 has a larger raceway (955 mm bore, 128 kg, C0a 3,750 kN), while the VSU250955 has a smaller raceway (855 mm bore, 115 kg, C0a 3,400 kN) — approximately a 10% difference in static axial capacity.

Q: How is a gearless slewing ring driven?

A: With no integrated gear teeth, the ring is driven by an external pinion on a machined OD, a chain or belt drive, a friction wheel, or a hydraulic or electric motor through a gearbox. The drive configuration is determined by the machine design.

Q: What precision classes are available?

A: P0, P6, and P5 are standard. Reduced-clearance and preloaded variants are available on request. Normal radial clearance is 0.03–0.13 mm.

Q: Is VSU251055 in stock?

A: Standard stock models ship within 5–7 days. MOQ is 1 pc. Contact Us to confirm current availability, request a CAD drawing, or obtain factory-direct pricing.

Contact Us

For pricing, availability, CAD drawings, or OEM replacement inquiries on VSU251055 Slewing Bearings, reach our engineering team at mia@hgb-bearing.com.