etz – Elektrotechnik & Automation reported on the safety of our machines. You can read the whole article below.
Niles-Simmons MC series CNC turn-mill machining centers enable economical, flexible, precise, and user-friendly complete machining of large, rotationally symmetrical workpieces in one clamping. For the N20 MC, N30 MC, and N40 MC machining centers, the risk assessment, verification, and documentation has recently been revised with the support of Wieland Electric’s safety experts.
Machine safety is a matter of trust in two respects. On the one hand, the operator trusts in the safe operation of a machine and thus in the care of the manufacturer. On the other hand, the equipment supplier relies on the expertise of internal or external safety experts to design and circulate their machines safely in accordance with the applicable standards and directives. For the machine manufacturer, a CE documentation that is coherent in content and structured is also a seal of quality that enables them to present themselves transparently to customers and thus generate lasting trust.
This kind of transparency also plays an important role for Niles-Simmons Industrieanlagen GmbH in Chemnitz, a leading manufacturer of machine tools for metal cutting. The company therefore decided to have the documentation for several machine tool types adapted by safety experts from Wieland Electric. “We have been looking for a reliable safety service provider for quite some time, because the so-called ‘view from outside’ is very important to us in risk assessment and verification,” explains Dirk Werner, team coordinator electrical design at Niles-Simmons. “Wieland Electric proved in a first project that we are in good hands here when it comes to safety service, which is why we finally received a follow-up order for two more machine types.”
CE process for a CNC machining center
Specifically, Wieland’s safety consultants have accompanied the CE process, first for a small CNC machining center from Niles-Simmons and then for two other machines of the same series. The machine-specific standards for the corresponding machine type were selected and applied, in this case the C standard DIN EN ISO 23125 (turning machines). In addition, the experts also used B standards such as DIN EN ISO 13849–1 (functional safety) and DIN EN ISO 11161 (integrated manufacturing systems) to implement safety.
In the course of the risk assessment, Wieland Electric’s safety consultants identified and evaluated all hazards and defined practicable risk reduction measures which comply with the applied standards. In addition, a safety concept was also drawn up for the respective machine types.
This was followed by the verification of the safety functions of the machine tools according to DIN EN ISO 13849–1. In order to provide mathematical proof that the execution of functional safety at least corresponds to the performance levels defined from the risk assessment, the Wieland experts evaluated all relevant circuit diagrams, documents, and parts lists, determined the safety characteristics of the components used, and confirmed the verification using a software tool. In the last step, the operating manuals of the machine tools were checked. These documents are crucial for the machine user to be able to operate machines safely in accordance with the regulations.
Modular system for risk assessment
Bernhard Scholz, sales engineer at Wieland Electric, knows only too well that the subject of safety is time-consuming and resource-intensive: “Honestly, very few machine and plant manufacturers have time to deal with machine safety intensively and comprehensively,” says B. Scholz. “Therefore, it is all the more important to have a partner at your side who provides the necessary expertise both customer- and application-oriented. We work together with the machine manufacturer to develop individual solution proposals and always adapt our approach to the needs of our partner.” Another joint project is already being planned, in which Wieland is developing a template in the sense of a modular construction kit for Niles-Simmons, which will enable the designers to carry out the necessary risk assessment for the respective function of the machines easily and safely themselves.
Author: Bruno Schäffler, Wieland Electric GmbH