Kinefac Introduces Forced Thru-Feed Spline Rolling to China
Unlike the traditional rack rolling method, Kinefacs process uses three cylindrical dies arrayed around the shaft. The dies are independently driven but maintained in precise rotational phase with respect to one another by a central splined phasing plug. This in turn engages the end of the shaft on which the spline is to be formed and drives it in a conjugate relationship with respect to the dies as shown in the diagram.
Teeth are formed by the action of the forming section at the front of the die and, once formed, are maintained in the correct axial position by the balance of the die teeth. The shaft is fed axially through the dies by a hydraulic cylinder operating on the opposite end of the shaft. This results in a low radial forming force on the body of the shaft, which makes it possible to roll splines on hollow parts. In addition, because of the feed-thru nature of the process, the three-cylindrical-die machine can also roll much longer