Industry 4.0 When machine tools communicate with each other
Germany - Two prototypes of a machining centre show the way towards digital production. The networked machines are equipped with sensors which initially supply the data. Intelligent evaluation in correlation with other data provides a new quality of statement of the machine status. By Jörg-Oliver Hestermann, Schaeffler Technologies
In order to raise the efficiency of production machines, it is logical to use the digitalisation of the value creation chain for highly promising solutional approaches. The main focus here is on providing data and corresponding evaluation processes which make the machine status more secure and can determine the characteristics of the workpiece more accurately. This is said to create added value for the machine operator in the form, for example, of higher machine availability, better machine utilisation, optimisation of production and process, or the possibility of judging the quality of the workpiece during or directly after production.
Schaeffler, a major user of machine tools itself, intends on the one hand to use these advantages for its own production and on the other hand to offer these possibilities to its customers. Schaeffler and Deckel Maho Pfronten, along with other partners, are therefore now presenting a machine concept called “Machine Tool 4.0”, which networks existing technology from the sensor all the way to the cloud using new digitalised components. This will represent a concrete step towards digitalised production.
Mill-turn machining centre as “4.0-capable” prototype
On the occasion of a new purchase, a project was launched to realise the requirements for a “4.0-capable” machine as the machine basis of a DMC 80 FD Duoblock mill-turn machining centre of the 4th generation. One of the two prototypes is in use in series production at the Schaeffler works in Höchstadt, the second will be on show at the DMG Mori stand at EMO 2015.
In order to realise this “4.0-capability”, the first need is for data sources in order to provide information on the current status and permit deductions to be made about the future behaviour of the components. In addition, sensors are integrated into all bearing locations relevant to the machining process and which record their current status. For, with machine tools, it is precisely the bearings that are the decisive components for machine performance, since they are also crucial for the quality of the workpiece.
A further step in order to integrate the machine into an Industry 4.0 environment is networking it as a connecting link in order to make the data available to all concerned. All additional sensors, actuators and also the evaluation units are connected to a network within the machine; a gateway releases the connection to the cloud. To guarantee data exchange with the machine control system, not only is the Profibus in the PLC used for time-sensitive and process-relevant data, but the OPC UA protocol on the human-machine-interface (HMI) is used for further information. The machine data is stored locally in the gateway and mirrored in Schaeffler’s own cloud. There is thus a guarantee that the data history is available at the machine even without network connections.