Slewing Rings is a kind of large size bearing. It can endure integrated load, and also can accommodate heavy radial load, axial load and incline moment of force. It is generally made up of mounting bore, inner gear or outer gear, lubrication bore and seal device. There are so many good character, such as compact structure, light weight, good rigidity, steady rotation, high orecision and safety etc. This bearing is widely used in the fields of engineering, metallurgy, mines petroleum, chemical industry, light industry, aviation, ports, shipping, war industry, instrument and meters, etc. Inner bore size ranges from 500mm to 4500mm.