Lifting heavy weights more easily

"In recent years, we have been able to record continuous growth with our solutions," explains Oliver Fett. He is plant manager at LTG AG in Weil der Stadt, Swabia, and the company's headquarters are in Zuffenhausen near Stuttgart. The supplier of ventilation and air-conditioning technology has been one of the pioneers in this industry for more than 95 years. Users receive, for example, high-performance fans, filter and humidification systems or volume flow and pressure controllers for their ventilation tasks. These are used, among other things, in building air conditioning in schools, offices and hospitals, or they fulfil the special conditions in manufacturing or processing operations - for example in the automotive, food or medical technology industries. "The steady growth led us to invest in our own laser cutting machine in December 2018," says plant manager Fett. The CO2 system from the manufacturer Trumpf is used in the sheet metal prefabrication area. Until then, the plant purchased the prefabricated parts externally.

The experts at Schmalz recommended a vacuum lifting device from the VacuMaster Basic 750 series for this task, which can be used to comfortably handle loads weighing up to 750 kilograms horizontally. Because the vacuum lifting device has a modular design, the right solution can be individually configured from various basic modules, operating elements, load cross beams and suction plates. The required suction force on the vacuum lifting device is generated by the vacuum generator and transferred to the workpiece via the suction plates. The suction plates are suitable for both smooth and slightly rough surfaces and are absolutely imprint-free. Uneven surfaces are compensated by spring plungers. The aluminium load beam also serves as a vacuum reservoir for safety. The operator can infinitely adjust the position of the eight suction pads on the crossbeam and thus handle different workpiece formats with one vacuum lifting device. The series is equipped with an acoustic warning device as well as a vacuum manometer with red-green display. "The operator handle allows the employee to control the VacuMaster in a way that is gentle on the body while maintaining the required distance from the load," says Oliver Fett with satisfaction.

For the lifting movement, Schmalz installed a column-mounted slewing crane made of aluminium with a chain hoist for loads of up to 1,000 kilograms and a slewing angle of 270 degrees. "To avoid collisions with the laser cutting machine, the slewing angle is limited," describes plant manager Fett. The five-metre jib also enables a large working area.

The sheets to be processed differ, among other things, in material quality, thickness or format: there is a choice of large-, medium- and small-format sheets. Their thickness can be up to 15 centimetres. "Depending on the order, the respective sheet metal panels are moved out of our high-bay warehouse in stacks in cassettes," Fett describes. He points to a stack. "Here we have large-format sheets with a length of three metres, a width of 1.5 metres and a thickness of four millimetres. One sheet weighs about 144 kilograms." The sheets are already decapitated. This means that thin surface films such as oxides or carbonates have been removed from the underlying metal to give them good adhesion for the subsequent electroplating. That is why completely impression-free handling is an important argument for LTG.

The operator picks up the top sheet from the stack with the vacuum lifting device VacuMaster and moves it to the machine table with the slewing crane. The aluminium of the crane reduces the dead weight and the operator can work for a long time without fatigue due to the smooth running. In addition, the process is very quiet. After laser processing, he removes the finished parts as well as the rejects manually without lifting assistance because these workpieces now only have low weights. "We manufacture these small parts for radial impellers," describes plant manager Fett. "We collect them on pallets and then transport them on to the assembly area." If workpieces cannot be handled with the vacuum lifting device because of their shape, for example in the assembly of the 150 to 200 kilogram driving wind simulators, LTG relies on belts attached to the aluminium column-mounted slewing crane.

"Our employees quickly accepted the VacuMaster," Oliver Fett is satisfied. "We are particularly enthusiastic about the advantages of the aluminium crane." Because compared to older systems from other manufacturers that LTG has in use, this one convinces with its ergonomic and smooth operation and simple assembly via a base plate. "With the vacuum handling system, we now significantly protect the health of our employees," says plant manager Fett. "But we also work extremely economically with it - especially in comparison to automated solutions."