Slew Ring Bearings
Slewing bearings are large- size bearings, which can carry combined loads: axial, radial load and tilting moment. They are usually equipped with fixing bolt holes, Internal or external gear, lubrication holes and sealing elements, consequently machinery structure can be made compact, guided rotary convenient, mounting and maintenance easy.

Available slewing bearings are: bearings with internal gear, external gear, external gear or non-gear, four-point contact ball bearings, double row angular contact ball bearings, cross cylindrical roller bearings and three row combined cylindrical roller bearings, among which four-point contact ball bearings have the higher static load carrying capacity while cross cylindrical roller bearings have the higher dynamic load carrying capacity. The pre-interference of cross-tapered roller bearings provides higher supporting rigidly and better rotary accuracy. with wider width and different raceways being capable of carrying any direction loads, three row combined cylindrical roller bearings have the same loads therefore compact machinery structure can be obtained. This is a kind of heavy-duty slewing bearings.

The typical applications of the slewing bearings: lift and transport machinery, excavation machinery, building machinery, harbor machinery, cargo lifting machinery on ships, and even high-precision radar antenna mounts and missile launching pads.

The Code Expressions of Slewing Bearings In this catalogue, there are two kinds of code expressions of LYC bearings

1. The code expression shown in the bore diameter and structure of bearings - there are two parts, basic-code and suffix. The expressions of type and structure of the basic-code are as follows:
Type and Structure Gear Form
Non-Gear External-Gear Internal-Gear
Four-point contact ball bearings 78000 178000 278000
Double row angular contact ball bearings 578000 678000 778000
Cross cylindrical roller bearings 79000 179000 279000
Cross tapered roller bearings 579000 679000 779000
Three row combined cylindrical roller bearings 539000 639000 739000
In the suffixed symbols, G shows that the bearing ring is made of 5CrMnMo steel. While G2 shows the ring is made of 50Mn.