Machine monitoring Switzerland: Unmanned production through process monitoring
Machine monitoring is a prerequisite for reliable, safe unmanned production. Bär und Mettler uses the monitoring system Artis CTM from Marposs.
Swiss Tool System is one of the world's most important manufacturers of system tools, specializing in spindle systems and holders for turning machining. Headquartered in Bürglen, Thurgau, Switzerland, Bär und Mettler AG is the production company for Swiss Tool System.
Productivity is pivotal
For finishing in their grinding shop, Bär und Mettler requires quality expertise more than anything else. Here, precision and accuracy must be ensured to a micrometre-level. In preliminary turning and milling, on the other hand, the main focus is on productivity. "Of course precise production is also essential in turning and milling, but productivity is the crucial factor here", explains Peter Heinemann, CTO at Swiss Tool System. He adds: "The machines must work reliably and unmanned around the clock."
For this purpose, appropriate machine tools were purchased and equipped with assistance systems to support unmanned operation. Bär und Mettler have chosen three Doosan Puma MX 2100 multi tasking turning centres for this work. This machining centre allows for complete machining of a part in a machine and with the milling head in its B-axis also a very flexible manufacturing of complex components.
The Doosan machines were equipped with the Marposs Artis CTM monitoring system, because Doosan's own monitoring system did not meet the demands of Bär und Mettler’s production.
"The Doosan system was simply not sensitive enough for our small tools and diameters," says P. Heinemann. He adds: "Also, it is important for us to measure parallel to main time. Thus, tool monitoring with mechanical or tactile systems was not suitable for us. Furthermore, we have already used Artis systems on our old machines."
Monitoring of complex machining processes with CTM
Influences on processes from machine, tool and workpiece must be reliably recognized to prevent damage and unplanned shutdowns. Maximising tool usage and avoiding scrap are essential to ensure and increase productivity. Bär und Mettler for example always operate two parallel tools parallel, which are monitored simultaneously. The main requirement of the selected tool, process and machine condition monitoring system Artis CTM thus was to monitor all process-relevant spindles and axes parallel. It was integrated into the machine via existing standard interfaces (Ethernet with FOCAS2). The machining processes are dynamically monitored using the existing digital control signals (DTA = digital torque adapter) of both spindles and the relevant five feed axis. This means that the Artis CTM system automatically selects the four most appropriate spindle/axle signals for real-time monitoring from the eight control signals. This allows for selective monitoring of the various tools, without the need for additional external sensors.