Rugged Heavy Metal Lifting

Lubas, a German machine and equipment manufacturer has made a name for itself when it comes to vacuum lifting systems for extremely heavy loads. “Our core business involves crossbeams for weights starting at 5,000 kilograms,” explains Alexia Bockermann, who is responsible for electro-technical planning and installation at Lubas. “Among the most powerful mass-produced lifting machines from the Lubas product line are the models from the UniTravMega series. Lubas is currently constructing two UniTravMega crossbeams with a lifting capacity of 15 tons each. The vacuum of each individual suction cup is recorded by Turck pressure sensors from the PS series and shown directly on site via the display. Lubas has installed two BL67 I/O stations to record and forward the measured values to the controller.

Temperatures in the limit range

Temperatures of over 200 °C develop directly on the sheets. While the special vulcanized elastomers of the vacuum suction cups can withstand temperatures of up to 250 °C, the electronics built into the top side of the steel structure are considerably more sensitive. “It isn’t just that the crossbeam is permanently positioned above the broiling hot sheets, but you have to account for an average temperature of 60 to 70 °C,” explains Bockermann. “This already places a high demand on the electronics.”

For this special environment, Turck has provided the right solution with the BL67 remote I/O station and pressure sensors from the PS series. “We are building the decentralized concept with the BL67 stations for the first time. We used to do everything using terminal boxes in the control cabinet. Rapid installation using M12 plug-in connectors and electronics modules is a considerable advantage,” says Bockermann, when explaining the company’s decision to use Turck products. The compact fieldbus stations are an additional advantage: For the BL67, Turck also offers Ethernet gateways that can be used to connect the lifting systems to the operator‘s company network. “This gives our customers the opportunity to monitor via their own company network how many tons the crane has moved or how many pipes have gone into production.”

Both BL67 stations used in the UniTravMega record the signals from the 53 pressure sensors installed above the vacuum suction cups. Their pivot and swivel displays make it possible to easily and directly check each individual vacuum suction cup and conveniently program them using only 3 push buttons, this makes laptops or other external programming devices redundant. “For security and maintenance of the crossbeam, it is very important to see whether a vacuum is established on each suction cup. Without the pressure sensors and the displays, each suction cup would have to be checked using a test plate. The customer can spare this expense and effort using pressure sensors,” explains Bockermann.