First-rate painting line
The crane components are up to 15 meters long – and later exposed to wind and the weather. For this reason, the manufacturer Liebherr attached importance to two aspects for the new painting facility: it had to be big and deliver high quality. They opted for WAGNER.
The coating of large workpieces presents manufacturers with exactly the same challenges. The Liebherr plant in Ehingen was thus looking for a customized solution to paint the components of its telescopic and lattice boom cranes that measure up to 15 meters in length. An impressive painting line has now been in operation there since October 2015 – it is equipped with four painting booths, several 1,000-liter paint containers, over 2,000 meters of pipes, 35 pumps, and five mixing and dosing systems from WAGNER. The system was planned, supplied, installed, and commissioned by THÜMA Maschinenbau und Service GmbH from Gotha.
Innovative loop line concept
The entire system consists of one central paint supply container and four painting booths; the largest booth measures 26 x 9 meters. In the paint supply room, the primer, top coat, hardener, and thinner are delivered and stirred in 1,000-liter containers, and supplied in separate stainless steel work containers for processing. Seven Puma 8-300 pumps from WAGNER transport the components at low pressure via the piping systems to the painting booths. "To bridge the large distances between the paint supply and the painting booths, and to be able to supply all ten painting guns uniformly, we have designed an innovative loop line concept with a switchover between the flow and return pipe," explains Tino Seifert, Managing Director at THÜMA. On the booths, 28 IceBreaker high-pressure pumps from WAGNER increase the pressure of the materials and supply the five 2K COMFORT mixing and dosing systems.
One special feature of the system concept is that minimal quantities of the subsequent top coat can be mixed in with the primer in each 2K mixing and dosing system. The white or gray primer is thus colored in such a way that the subsequent top coat application is optimized and has a more brilliant appearance in the end. "COMFORT is actually a 2K system, based on which the WAGNER Development Department has developed a 3K version. The AIS dosing system automatically controls not only the injection of the hardener, but the quantity of the top coat as well," explains Tino Seifert.
Liebherr is satisfied with the advice and products provided. "THÜMA and WAGNER have accompanied us throughout the entire process and made their expertise available to us. This was a key factor to our success," says Thomas Nüssle, Head of Surface Finishing. "In all likelihood, the close collaboration will continue in future."