Protection and Safety without Compromises
Where other protective measures fail -
EAS-torque limiting clutches won’t let you down
Damages caused by col l isions and production downtimes are expensive and detrimental to the company image, and must therefore be prevented or minimised whenever possible. There are several concepts for damage prevention or early detection on the market. However, the continuing trend towards higher working speeds and morerigid machine constructions sets boundaries for most protect ion concepts. But not for the mechanical torque limiting clutches, which can use their characteristics to their full advantage in such condi t ions. mayr power transmission is the world leader in the field of torque limiting clutches and has been able to prove the impressive protect ive ef fects of i ts EAS-torque limiting clutches in extensive test series on a collision test stand.
- Fig. 1: Destroyed contact surfaces of a ball thread drive. Components with such preliminary damages can be monitored via Condition Monitoring and can be replaced on time during preventive maintenance work before a total breakdown.
In times of global competition, production companies are required to pay more attention to the high availability of their machines and systems. Increasing cycle rates and work speeds are means to ensure that the “Production Site Germany” remains secure and capable of expansion. Therefore, any errors occurring in the process chain, which lead to collisions and damage in the systems, have a more and more serious impact. This can mean both direct mistakes made by the machine operators and mistakes in the definition of tools, workpieces or the respective programmes. There is the risk of long and expensive system downtimes or an immediate or gradual deterioration in process safety.
Several strategies have been established in parallel to prevent damages through collisions, to minimise them or to recognize them as such. Accordingly, a distinction is made between Measures for Preventive Collision Protection and measures for damage diagnosis, also known as Condition Monitoring. In Condition Monitoring, the state of essential machine components such as bearings, ball thread drives or linear guides is monitored. Monitoring takes place either permanently, in regular intervals or, dependent on the demand, via acceleration sensors, which are placed in suitable parts of the machine.
During permanent monitoring, even preliminary damages caused by collisions can be recognized immediately. To do this, the signal pattern of the machine in its current state is compared to the signal pattern in new condition. The difference enables the user to draw conclusions as to which parts are damaged. These parts can then be replaced during the preventive maintenance work. Damage like that shown in Fig. 1 can be detected using this method. Therefore, Condition Monitoring does not represent protection for a machine or its components per se; but is used mainly for guaranteeing process safety and for minimising downtimes.