Increased safety for tyre-curing presses

Sick has been working with tyre manufacturer Continental to improve safety on its tyre-curing presses, which are in use at 16 locations around the world. Continental was seeking to equip the presses with a uniform, global safety concept while achieving optimum ergonomics and flexibility.

Initially, a comprehensive risk assessment was carried out on a range of typical tyre-curing presses and Sick Safety Services also carried out an external risk assessment to provide Continental with a second opinion and verified their own findings.

These comprehensive findings were then used to create a safety concept. This took into account all the mechanical risks at the front of the press as well as those at the sides, rear and underneath. The safety concept, along with its requirements for the implementation of the safety solutions, is now the basis for the global rollout. For example, to provide protection at the side and rear of the presses, different options such as safety light curtains and safety doors or barriers with safety switches can be used. Under the press, physical guards are used. At the front of the press, where the workers operate the press and the most important hazardous area protection is required, safety laser scanners are the most appropriate means of protection.

Continental then carried out a comparison of different safety providers, taking into account globally available and certified safety services, support for the implementation and rollout of the project, the creation of electrical documentation, commissioning and the critical final safety acceptance of the machine in each country. Continental ultimately chose Sick to provide their products and services.

Alongside high safety requirements, efficiency and the approval of the machine operators are crucial for Continental. A high level of flexibility when operating neighbouring machines and best use of available space were key factors for this application. The integration of all a machine’s safety components with short shutdown times and quick commissioning were also important. Sick set to work on these requirements and developed what was then a unique solution for Continental utilising the S3000 safety laser scanner and the Flexi Soft safety controller. Just one safety laser scanner covers up to four protective fields simultaneously, ie, without protective field switchover and thus without additional response times and without unnecessarily shutting down neighbouring machines. This means that four dangerous movements, either from a machine or from neighbouring system parts, can be covered. This ensures maximum flexibility when operating adjacent machines and production processes - with minimum hardware requirements.

In contrast to sequential switching of individual protective fields, no switchover and sequential evaluation is necessary for monitoring simultaneous protective fields with the S3000 safety laser scanner. As a result, the response time is several times faster than that of other safety laser scanners available in compatible system configurations. Smaller and therefore more space-efficient protective fields can therefore be designed. The safety laser scanner reports everything that the S3000 detects during a scan directly to the Flexi Soft safety controller. Here, cut-off paths and the cut-off behaviour can be configured easily.

“The safety of the tyre-curing presses is very important to us,” emphasises Timo Kuss, global project manager and plant engineering manager at Continental in Aachen, Germany. “Which is why we need a partner that we can rely on to deliver the necessary services and machine acceptance processes throughout the world.” Sick is currently supporting the simultaneous rollout of the safety concept step by step in up to 16 countries.