Since 1993, storage and sawing technology from the German company Kasto (www.kasto.com), which has a UK subsidiary in Milton Keynes, has provided service and equipment to hydraulic-equipment manufacturer Liebherr-Components Kirchdorf GmbH.

To meet increasing demand for its hydraulic cylinders, the latter decided in 2019 to modernise and expand its production systems; it commissioned Kasto to upgrade the existing storage system for steel bar and tube — along with one of two bandsaws — and install a customised robotic handling system.

Liebherr-Components has specialised in the production of hydraulic cylinders since 1958. About 75,000 hydraulic cylinders, ‘suspensions’ and system solutions for cylinders leave the plant every year to be used world-wide. Stefan Lützel, who works in the industrial engineering department, said: “A Kasto cassette storage system with 733 locations, an automatic cantilever arm and a large bandsaw from the KastoHba series had provided reliable service for 26 years.

“Until recently, a production circular saw of a similar age from the same manufacturer was also in use. However, we gave this saw a well-deserved retirement in 2016, when we modernised our sawing technology and increased our cutting capacity to 430mm in diameter with the addition of a KastoTec SC 4 bandsaw, which is particularly effective at processing difficult-to-cut materials.

“This saw, which can operate with either a high-speed-steel blade or a carbide blade, is equipped with the Kasto Performance Cutting (KPC) package, which includes improved band guidance and vibration absorption for even higher cutting efficiency.

“The bar storage system and KastoHba bandsaw were still in good mechanical working
condition, but the drives, measuring systems, controls and cabling needed modernising. Kasto offered a turn-key package to update them, as an economical alternative to replacing these two pieces of capital plant and at the same time bring safety features up to current standards.”

Magnetic grippers
Furthermore, Liebherr-Components and Kasto jointly developed a solution to automate the handling of cut pieces, with an industrial robot moving between the two saws on a linear track. The robot is equipped with several exchangeable magnetic grippers designed to pick up various cut lengths (weighing up to 350kg) from the sawing machines.

Along the linear axis, there are 18 storage locations for pallets and containers, the position of each being stored in the robot’s control system. The cut pieces are finally transported to another location in the factory by lift truck for further processing.

Mr Lützel said: “It was a major advantage having a single partner undertake all this work, as it avoided having to co-ordinate the activities of different suppliers. This was especially important, as we had to carry out the work while the factory continued operating, without causing too much disruption. Thanks to excellent organisation by Kasto, everything ran smoothly.”

The benefits to production within the Kirchdorf factory include a reduction of the noise level in the working environment, as the robot places cut pieces quietly in their designated location; before, they used to drop noisily into a bin. Robotic placement also means that chrome-plated material remains undamaged after it is sawn.

Further improvements include: the ability to ‘undertake material cuts up to 3m in length’; a higher quality of cut than before; shorter processing times; a minimum of waste; and a significant increase in production efficiency.

An operator simply enters a cutting order at the control, whereupon the gantry crane in the storage system automatically transfers the required bar to one of the two saws, where the material is cut, and the pieces are handled and sorted — again without manual intervention.

It is not only a safe operating environment but also one in which long periods of unattended production are possible.
Mr Lützel says that since the system has been in operation, it has run reliably, without any noteworthy disruptions and with high availability.

He also said that if any problems do arise, the equipment can be monitored remotely by engineers at Kasto’s headquarters in Achern.