With the development of modern technology, machining equipment industry on more advanced, for a rotary union, it is a new type of use. For the present, spindle machining centers need to use high-speed rotary joint, this joint belongs to a unidirectional transmission medium, no recovery media, mainly used for cooling the workpiece in machining center, only a single loop can be used, the general operating parameters: speed at 3000RPM-5000RPM, working pressure 50bar-100bar, temperature below room temperature, the product of the seal requirements are very strict, mostly by mechanical seals, mechanical seal is characterized by a small torque, good sealing performance, and long life.

Machining center with high-speed rotary union, mainly through threaded connections, in general, cosmau standard product is M16X1.5 anti-tooth connection, this threaded connection, the device always in one direction of rotation, can only rotate forward and not reversed at the same time, or will cause screw loosening. Internal structure of the main play by spring mechanical seal, when the medium introduced into the rotary internal fittings, connectors inside the spring will cause some pressure on the top upwardly spring structure, a spring above with alloy plane which requirements are very smooth, like a mirror, like the bottom of the upper end of the rotor is made of alloy, two smooth alloy contact, spring withstand, thus forming a spring-loaded mechanical seals, inside the upper end of the high-speed bearings imported P4 while requiring precision rotor and the stator portion of the requirements of concentric, if eccentric rotation occurred, would greatly reduce the service life, it affects the life and sealing performance of the rotary joint.

With the slow development of the machining industry, the use of high-speed rotary joint will slowly spread, species will also be gradually extended. In future machining center industry, high-speed rotary joint application will be a major breakthrough.