Fritz Studer Built-in EDM dressing system will increase grinding energy
Editor: Thomas Masuch
Switzerland – With Studer-Wiredress, Swiss grinding specialist Fritz Studer brings a dressing machine to the market that makes use of the wire erosion precept and is totally built-in into the grinding machine and its management system.
The built-in electro-discharge dressing know-how Wiredress opens up brand-new potentialities for grinding with metal-bonded grinding wheels and drastically cuts auxiliary instances. In line with Studer, it has been attainable to extend grinding energy within the grinding course of by 30% and scale back grinding wheel put on by 70% as compared with ceramic and resin bonds. Grinding wheels with very intricate contours will also be dressed.
Electro-discharge dressing for metal-bonded wheels
Steel-bonded grinding wheels provide explicit advantages when engaged on difficult-to-machine supplies equivalent to high-alloy, hardened steels, tungsten carbides and ceramics, Studer defined. Such wheels are mentioned to supply superior dimensional and thermal stability and dissipate the warmth produced by grinding extra shortly. Nevertheless, along with some great benefits of steel bonds, there are additionally disadvantages, as dressing these wheels entails larger expense and energy. Dressing with silicon carbide wheels, for instance, typically doesn’t obtain passable outcomes, and complex profiles are usually not attainable. The built-in Wiredress system solves these issues.
The dressing machine is in precept a small wire erosion machine. The electrode is a wire, which is drawn with a small hole tangentially previous the machining level at a relentless pace of 100 mm/s. The other pole is the grinding wheel, which strikes at peripheral speeds of fifty to 140 m/s throughout dressing.
It doesn’t want any dielectric, because the grinding oil used throughout grinding fulfills this operate. The dressing wire is guided in a groove on the circumference of a skinny, round ceramic disk. The ceramic disk has a notch the place the sparks bounce between the wire and the wheel.
Electrical discharge dressing processes use the fundamental precept of EDM machines, which have been used for precision machining for a few years. As with these machines, the fabric is eliminated with out contact by extraordinarily brief direct present pulses following one another in fast succession, which generate a discharge within the hole between electrode and workpiece within the dielectric, Studer mentioned. Through the discharge, tiny areas of the steel bond of the grinding wheel are melted and flushed out of the hole.
In line with the corporate, the grinding wheel by no means needs to be eliminated for dressing. Because of the excessive proportion of grain house, the wheel could be very free-cutting. The dressing intervals might be longer. Nevertheless, because the dressing course of requires so little expense and energy, very complicated contours will also be dressed at shorter intervals, Studer added.
Dressing unit accommodates ten kilometres of wire
Feeds of 15 to 25 mm/min might be achieved when dressing a typical steel bond. On this manner, largely free geometries and complex contours with inside radii of 0.2 mm and exterior radii of 0.05 mm are generated on the grinding wheel. Elimination charges of as much as 80 mm3/min are achieved, Studer mentioned. The grain retains its unique form throughout this contactless dressing course of.
The wire reel within the dressing unit accommodates ten kilometres of wire; this provide would permit dressing to be continued for approx. 16 hours with out interruption. The used wire is lower into brief items instantly after the dressing course of and picked up in a container.