SWIVEL JOINT FOR CONSTRUCTION MACHINE

摘要

A swivel joint for a construction machine, which has improved dust resistance and ensures higher efficiency in replacement work. A spindle 13 of a swivel joint 11 is mounted to an upper track frame 2a, and a body 12 is rotatable together with a swing structure main frame 1 in an opening 15 formed in the swing structure main frame 1 through engagement between a stopper projection 16 and a stopper plate 17. Tubes 21 on the swing structure side are connected to an upper end surface of the body 12 by using fittings 22 in concentrated layout, and tubes 23 on the travel structure side are connected to a lower portion of the spindle 13 by using fittings 24. The body 12 has thicker wall portions 31, 32 in sidewalls thereof, and a plurality of axial passages 33, 34 communicating with a plurality of circumferential grooves 41 are formed inside the thicker wall portions. The plurality of axial passages are opened at the upper end surface of the body, and the tubes 21 on the swing structure side are connected to the upper end surface of the body in concentrated layout.