Slewing Bearing for Swing Tower Support (DTR Type)

How to choose Slewing Ring Bearings

Points to check when selecting, with the values for this product (Slewing Bearing for Swing Tower Support (DTR Type)).

1. 1. Select a structure that suits load and moment

   Single-row ball type is compact and suited to general construction machinery and cranes; three-row combined cylindrical roller type offers high rigidity and rated load for large cranes and tunnel boring machines; double-row tapered roller type can carry high axial load thanks to its large contact angle. Select the type based on the magnitude of moment load and impact.

2. 2. Allow margin in static rated load

   Because slewing bearings often operate at low speed or oscillate, the basic static rated load in the axial direction, C0a, is the primary selection criterion. Listed products range widely from 341 to 394000 kN. Convert maximum load and moment to equivalent load, and compare products with a safety factor appropriate to the application.

3. 3. Match mounting diameter and support structure dimensions

   Bore diameter d and outside diameter D determine the mounting surface on the support structure or rotating body, the bolt hole layout, and the space for piping and cables passing through the center. Listed bore diameters range from a few mm to 6457 mm. For large-diameter products, a split design makes transport and assembly easier.

4. 4. Confirm gear position and specifications

   Whether to choose ungeared, internal-tooth or external-tooth types depends on the layout of the drive pinion. Listed products have a pressure angle of 20°. Match the tooth profile (standard or low-profile teeth) and the JIS gear accuracy grade with the pinion side, and consider surface and root induction hardening as required.

5. 5. Select sealing and lubrication method for the operating environment

   In environments exposed to soil or water pressure, some products offer pressure-resistant seals with a static withstand pressure of 0.3 MPa in addition to labyrinth and dust seals. Check the presence of grease nipples and drain ports, and whether grease feeding, oil bath or forced circulation lubrication is used, in line with the maintenance plan.

6. 6. Estimate handling and installation method from mass

   Listed products vary widely in mass, from 1 to 45800 kg. Large units are constrained by lifting equipment, crane capacity and transport dimensions, so verify the mass and, if necessary, consider circumferentially split designs (two-piece or four-piece).

This guide was written by AI based on the listed products' documents and specification items.

About Slewing Ring Bearings and all products

Description

Structure with either the inner or outer ring split into two parts, combining three raceway rings and three rows of cylindrical rollers. Sealed with labyrinth or dust seals, etc., and available in sizes from small to extra-large.

FAQ

Q. What loads can the DTR type slewing bearing accommodate?

A. It is a high-rigidity slewing bearing that accommodates radial, axial and moment loads. Its key features are its heavy-load, high-rigidity design.

Q. What are the internal structure and sealing method of the DTR type slewing bearing?

A. It has either the inner or outer ring split into two parts, combining three raceway rings and three rows of cylindrical rollers. It is sealed with labyrinth seals, dust seals, pressure-resistant seals, etc., to prevent foreign matter ingress.

Q. What size range does the DTR type slewing bearing cover?

A. It is available in sizes from small to extra-large.

Q. What applications is the DTR type slewing bearing used for?

A. It is used for supporting swing towers.

Written by AI based on the content of the source documents.

Source documents

• Catalog 連続鋳造設備用軸受と関連商品 Open page 11
  Found on: https://koyo.jtekt.co.jp/support/catalog-download/