Fast production of high quality surfaces

The high speed ROBOFORM 350/550 die-sink machines reduce cycle times without compromising on part quality and surface finish. The machines – the ROBOFORM 350/550S – are aimed at precision engineers involved in machining pre-roughed 3D cavities and who manufacture complex parts with deep rib features. The unique selling proposition and attraction of the machines is their speed, responsiveness and ability to deliver super-fine and homogeneous surface finishes (>Ra 0.4µm) on complex parts. The machines are equipped with a fast z-axis (7.5m/min) – twice as fast as the z-axis movement on earlier 350/550 models – and can achieve acceleration rates of 5m/s2 – an improvement of 500 % on previous machines. In benchmarking trials using a graphite electrode to machine a 70mm deep cut in a steel workpiece, the new ROBOFORM machines achieved the desired result in just 2 hours 24 minutes – 25 % faster than on other EDM machines. In addition to their fast z-axis speeds and acceleration, the machines’ fast pulsation speeds help improve evacuation of debris/particles located in the spark gap (critical when machining deep ribs, cavities etc.) which in turn also helps optimise the EDM machining process in terms of faster stock removal rates, improved surface finish and increased electrode life. Productivity and performance benefits are further ensured when the ‘Speed Finishing’ settings are selected on the machines. Irrespective of the dimensions of surface to be machined, precise and delicate features can be reproduced to exacting standards with significantly reduced less electrode wear. This is achieved via an integrated high-performance micro-fin generator unit connected to the machining head. This technology configuration - plus sophisticated adaptive software - enables the machine to monitor and predict cutting conditions that exist/that are likely to exist in the spark gap. This information is processed quickly enabling the machine to respond instantly (in real time) to the changing conditions. This facility means that the required results in terms of accuracy, surface finish, removal rates etc. are not affected or compromised. In trials using the ‘Speed Finishing’ settings – a surface finish of Ra 0.5 µm was achieved in 6 hours in a 60 cm x 60 cm x 0.5 cm cavity. With other EDM machines a similar result was achieved in 18 hours! The ROBOFORM machines are equipped with the latest DPControl system (Version 2.1). This powerful control system is operator friendly and is simple to use. To save time and reduce potential programming errors or omissions – new features and capabilities have been incorporated.