When will hard turning and grinding combination machining be the norm?
22/02/2015 - Oliver Hagenlocher
At the end of production, workpieces must go through a grinding process to achieve the desired surface quality: this has been the standard in manufacturing for various reasons. First, hardened workpieces could not be processed with standard turning. Second, besides grinding no other technology was capable of producing the required surface finish. Hard turning changed all of this, allowing hardened metals to be effectively turned. This naturally led to the combination of hard turning and grinding in order to reap the benefits of both technologies: the speed of turning with the surface finish of grinding. So the question remains, when will this combination machining establish itself on the market? The practical answer: the technology is here, ready to be used when and where it makes sense.
Let’s take the example of a sprocket wheel, which ultimately consists of three surfaces in need of machining: two faces on either side of the workpiece and a drilling operation. Inner diameter grinding is used for the perfect finish of the drill holes where only minimal amounts of material need to be removed for a top surface finish. The amount of material needed to be removed from the faces, however, is much higher, making turning the most efficient choice. How this process develops varies from workpiece to workpiece, thus making flexibile machines of utmost importance.
The EMAG VLC 100 GT, for example, allows the work area to be freely configured, whether it is with OD and ID grinding plus turning capabilities or designed with two turning and one grinding operation.