Slewing rings – find manufacturers and suppliers

Slewing rings are bearing components that support large axial and radial loads as well as tilting moments and simultaneously enable rotary movement between two components.

They are typically used in machines, cranes, wind turbines and heavy vehicles where precise rotary movements under high loads are required.

Below you will find the functionality, structure, movement principle, designs and areas of application of slewing rings, as well as their advantages:

How slewing rings work:

Design and components of slewing rings:

1. Inner ring and outer ring - Stabilize the movement and transmit forces.
2. Rolling elements (balls or rollers) - Ensure low-friction rotary motion.
3. Seals - Protect the bearing from dust, water and contamination.
4. Lubrication - Reduces wear and ensures a longer service life.
5. Gear rims (optional) - Enable direct power transmission via gear wheels.

Movement principle of slewing rings:

1. The rolling elements roll between the inner and outer ring to minimize friction.
2. Depending on the design, they can absorb axial, radial and tilting moments.
3. In the case of toothed slewing rings, a drive element (e.g. motor with pinion) ensures rotation.

Types of slewing rings:

1. Single-row ball slewing ring - Low friction, for lighter loads.
2. Double-row ball bearing slewing ring - Higher load capacity due to two rows of balls.
3. Single-row roller bearing slewing ring - Higher load capacity than ball bearings, for heavy loads.
4. Double-row roller bearing slewing ring - Even higher load capacity, for extreme applications.
5. Three-roller bearing - Particularly robust for crane systems and heavy industry.
6. Slewing rings with internal or external ring gear - Direct power transmission through pinion drive.

Application areas for slewing rings:

1. Construction and heavy industry:
Excavators and cranes - Slewing ring bearings enable the rotation of booms.
Concrete pumps and conveyor systems - Stable slewing rings for precise movements.
Tunnel boring machines - Control and positioning of large boring heads.

2. Wind turbines:
Rotor blade bearings - slewing rings regulate the blade angle (pitch system).
Azimuth systems - adjustment of wind direction for maximum energy yield.

3. Mechanical and plant engineering:
Rotary tables and machining centers - Precise positioning of heavy workpieces.
Filling and packaging machines - Precise rotation in automated processes.

4. Transportation and vehicle construction:
Heavy-duty transporters and turntable ladders - Movable platforms for fire departments and the military.
Rail bogies - Connecting elements between bogies and wagons.

5. Medical technology:
CT scanners and X-ray machines - Precise, quiet rotary movements for high-resolution images.
Surgical robots - Precise swivel movements for minimally invasive procedures.

Advantages of slewing rings:

• High load capacity - Absorption of axial, radial and tilting moments.
• Space-saving integration - Replaces several bearings in a compact design.
• Versatile applications - Can be used in industry, mechanical engineering, wind power and medical technology.
• Low maintenance - Long service life with correct lubrication and sealing.
• Direct drive options - Gears or motors can be coupled directly.

Slewing rings are indispensable components for industrial, construction and medical technology applications. They enable smooth rotary movements under high loads and are available in various designs for specific requirements. The right choice of material, lubrication and maintenance ensure a long service life and high operational reliability.

Here you will find the most important aspects to consider when purchasing slewing rings:

The purchase of slewing rings requires a thorough analysis of technical specifications, operating conditions and economic factors. Slewing rings are critical components in construction, machine and wind power plants, so precision, load-bearing capacity and durability are essential.

• Before purchasing slewing rings, the specific requirements must be analyzed in detail.
• Slewing rings are available in various designs, depending on the load and application:
• Single-row ball slewing ring - Low friction, for light to medium loads.
• Double-row ball bearing slewing ring - Higher load capacity due to two rows of balls.
• Single-row roller bearing slewing ring - Higher load capacity than ball bearings, for heavy loads.
• Double-row roller bearing slewing ring - Particularly robust for high axial and radial loads.
• Three-roller bearing - For extreme loads and high tilting moments, e.g. in cranes.
• Slewing rings with internal or external ring gear - For applications with direct power transmission via a pinion.
• Determine the requirements for load capacity and load types:
• Radial forces - Lateral load due to horizontal movement.
• Axial forces - Vertical load due to weight or compressive forces.
• Tilting moments - stress due to uneven load distribution.
• Static and dynamic load ratings - consideration of long-term durability.
• The choice of material and the required corrosion protection are important selection criteria.
• Heat-treated steel 42CrMo4, 50Mn - High strength for heavy-duty applications.
• Stainless steel X30CrMoN15-1 - Corrosion-resistant for maritime or medical applications.
• Surface coatings using zinc, nickel, PTFE, Geomet®) - Protection against corrosion and wear.
• Hardened raceways - Extended service life under high loads.
• Should there be toothing and how can the drive be designed?
• Toothless - Freely rotatable, must be driven externally.
• Internally toothed - Protection of the toothing against external influences, compact design.
• Externally toothed - Easier power transmission, but more exposed.
• Pay attention to the module for the gearing - ensure accuracy of fit with the drive pinion.
• Which seals are useful and how can lubrication be ensured?
• Rubber seals such as 2RS, LLU - protection against dust, water and dirt.
• Grease lubrication using lithium, calcium and PTFE greases - standard for industrial applications.
• oil lubrication for high-speed applications - Reduces friction in precision systems.
• Is temperature and environmental resistance important?
• Standard versions -20°C to +80°C - For normal applications.
• Heat resistant versions >200°C - For high temperature applications such as steel mills.
• Corrosion-protected models - Particularly important for offshore, port or chemical industries.
• Observe certifications and standards: ISO 9001 for quality management, ISO 14001 for sustainable production, specific industry certifications e.g. ISO 16949 - Especially for automotive industry, ISO 492 / DIN 620 / ABEC tolerance classes.
• When purchasing, don't just pay attention to the purchase price. Cheap versions often have a shorter service life and require frequent replacement.
• Ensure regular lubrication during operation. Especially in heavy-duty applications.
• Check the seals regularly. Damage can lead to dirt ingress and bearing wear.
• Do not forget to carry out wear and corrosion checks. Early fault detection prevents failures.

Purchasing slewing rings requires detailed knowledge of the technical requirements, careful supplier selection and an economical procurement strategy. The right choice of material, design and lubrication make a decisive contribution to the service life and efficiency of the slewing ring. High-quality slewing rings minimize maintenance costs and prevent unplanned breakdowns.

Slewing rings can be purchased from various suppliers. You will find comprehensive information on manufacturers and suppliers of Slewing rings around the world on Exportpages.