Circular arc end tooth coupling can be divided by two kinds, firstly is straight tooth (vulgo called “Hirth”) and the second is called “double curved surface arc end face tooth”which is mainly used on the batch-type location just like the high precision locating and high rotation speed torque. For example, machine tool blade spire, rotating table, robot joint, Medical Devices and big high rotation speed centrifugal compressor drums with lobed wheel, gas turbine corona, aero turbine engine, high-power engine, high power gear case, navigation propeller turbine blade, high speed locomotive bogie hollow shaft big high rotation speed device etc.

By the special tooth shape , the“surface arc end face tooth”can assure self-centering ability of the production ,more contact area of the tooth, higher hardness both tooth surface and the end with higher meshing precision transferring bigger twisting force to overcome the influence from the outside force under the 60,000-80,000r/h and deformation of materials. In the mean while it can also divide the complex massive structure into several simple structure to be convenient for designing, producing, installing and maintaining.