Excavator Slew Bearing

What is Excavator Slew Bearing?

A slew or slewing ring enables machinery to perform rotational movements. They combine traditional bearing elements with gears and mounting holes, which allows the ring to connect directly to a structure for maximum versatility.

Excavators lift, turn and spin frequently to move materials or perform other duties, requiring a system that can rotate as desired. The slew ring's hybrid format facilities this movement in an excavator, allowing heavy construction equipment to swing and turn smoothly, even when handling heavy loads.

A slew ring mounts horizontally between the excavator's house and undercarriage. This placement lets the machine and its attachments swing nonstop as necessary.

These rings typically consist of an inner ring, rolling elements, two seals and an outer seal. Each part plays an essential role in the system's function. The outer ring connects with the excavator, offering stability, while the inner ring facilitates movement with the ball- or roller-style bearings. The seals help lubricate the rolling elements properly.

Features of Excavator Slew Bearing

Excavator slew bearings, also known as slewing bearings or turntable bearings, are large-diameter rotational bearings that support heavy axial, radial, and tilting moment loads. They play a critical role in the operation of an excavator by enabling the smooth and controlled rotation of the upper structure, including the cab, boom, and arm, relative to the undercarriage.

Key features of excavator slew bearings include:

Large diameter: Excavator slew bearings typically have a large diameter to effectively distribute loads and handle various forces during the excavator's operation.

Rolling elements: The bearings consist of an inner and outer ring with rolling elements – usually balls or cylindrical rollers – between them. The rolling elements help reduce friction and allow for smooth rotation under heavy loads.

Raceways: Both the inner and outer rings of the bearing have raceways, or groove tracks, machined into them to accommodate the rolling elements. The raceways need to be precisely manufactured to ensure smooth rotation and proper load distribution.

Seals: Slew bearings in excavators generally have seals in place to prevent the entry of contaminants such as dirt, dust, and water, prolonging their service life and maintaining optimal performance.

Load capacity: Excavator slew bearings are designed to handle heavy axial, radial, and tilting moment loads simultaneously while providing stable and controlled rotation.

Material: Slew bearings in excavators are typically made of high-quality, hardened steel to ensure strength, resistance against wear, and reliable operation under heavy loads and harsh operating conditions.

Lubrication: Lubrication is critical for reducing friction and wear in the bearing. Grease, which is the most common lubricant in excavator slew bearings, can be regularly added through designated lubrication points to minimize friction, wear, and corrosion.

Ease of maintenance: Excavator slew bearings are designed for easy inspection and maintenance, with accessible lubrication points and replaceable wear parts to ensure a longer service life and reduce downtime for repairs.

Where is the slew ring in an excavator?

In an excavator, the slew ring is located between the upper structure (also called the house or revolving frame) and the undercarriage (also known as the lower structure or track frame). The slew ring acts as a large-diameter rotational bearing, which facilitates the smooth and controlled rotation of the upper structure relative to the undercarriage. This rotation allows the excavator to maneuver its working equipment, including the cab, boom, arm, and bucket, over a wide area without needing to frequently reposition the tracks.

The slew ring consists of an inner and outer ring with rolling elements, typically balls or cylindrical rollers, between them. It is designed to handle various forces, such as axial, radial, and tilting moment loads, while performing excavating and material handling tasks. Proper lubrication, regular inspection, and maintenance of the slew ring are necessary to ensure the durability, reliability, and efficiency of the excavator.

Excavator bearings, particularly slew bearings, come in a wide range of sizes to accommodate the varying dimensions and load capacities of different excavators. The size of an excavator bearing depends on factors such as the excavator model, operating weight, working equipment capacity, and intended application.

Size of Excavator Slew Bearing

For a slew bearing, the size is typically specified by its outer diameter, inner diameter, and height or width. The dimensions can range from small slew bearings with outer diameters of a few hundred millimeters for mini or compact excavators to large slew bearings with outer diameters of several meters for heavy-duty mining or construction excavators.

Supplier of Excavor Slew Bearing

For sourcing excavator slew bearings, consider researching reputable manufacturers and suppliers that specialize in heavy equipment parts. Zenith Drive is a professional slew bearing manufacturer for sourcing any types of excavator slew bearings. If you are looking for excavator slew bearings, feel free to contact us.