Heavy steel rolls, called coils, are used in many operations. A wide variety of workpieces can be produced from the rolled-up sheet steel. That's why the material is in demand: after the Corona pandemic depressed steel consumption by around 13 percent in 2020, according to the steel association Eurofer, it is expected to rise again in the current year 2021, almost reaching the level of 2019 at around 152 million tons.
Profiles made of steel sheets can be found in almost every industrial sector – from automotive and construction, where most steel is used, to power generation and agricultural engineering. Welser Profile GmbH, headquartered in Ybbsitz on the Lower Austrian Iron Road. Production site in Bönen near Dortmund specializes in steel profiles of all kinds. Its products are used in the new night trains of the Austrian Federal Railways as well as in large photovoltaic systems – and that worldwide. In the rollform procedure, the experts have since 1960 already more than 23.500 unique profile cross-sections realized for individual requirements in virtually all industries.
Quick help for material fatigue
Two process cranes work in the coil warehouse in Bönen, Germany, where they have to transport the raw material for profile production safely and reliably. An inspection by experts from Konecranes and Demag Services reveals that the girder of a Demag crane has cracks between the endcarriage and the crane bridge, making it unserviceable. "In the course of a crane's life cycle, it has to pick up and transport heavy loads again and again," explains Sascha Oppenhäuser, Director Service EMEA Central North at Konecranes. "Inevitably, material fatigue occurs as the crane gets older."Cracks in the beam mean: The crane can no longer be used in this way. This is poison for productivity in the plant, because without steel sheets, no profiles can be produced either. There is no alternative for transporting the rolls, which can weigh up to 30 tons. To stabilize the girder in the short term, Konecranes' experts carried out an emergency repair. Sascha Oppenhäuser: "In the process, the cracked areas will be cut out of the crane girder and replaced with fresh, fitted steel parts." However, this tried-and-tested method of repair is only a short-term stopgap measure, as it changes the shape and structure of the girder, which significantly increases wear and tear.
Teamwork for effective modernization
In addition, the inspection had revealed that the crane runway was also badly worn. "The crane runway and the trolleys are among the main wear parts on any plant," emphasizes Sascha Oppenhäuser. "The demands on the cranes often change over time – where in the past, for example, only 15 tons had to be lifted, today it can be as much as 30 tons. However, the original crane runways were mostly not designed for this purpose." A long-term oriented. Future-proof modernization of the crane therefore makes sense. " A long-term oriented. Future-proof crane modernization therefore makes sense. Konecranes' experts create an overall concept for this, from parts ordering to acceptance. Time is an important factor here: the damage was detected in mid-2020 and repaired by emergency repair, and the modernization should be implemented by the beginning of 2021. For an optimum result, the Konecranes and Demag service and modernization team works together with its colleagues from subsidiary KSR. They specialize in upgrading crane runways and are taking on this part of the project, while Konecranes experts are focusing on replacing the trolleys on both process cranes in the coil store, replacing the entire bridge of the damaged crane, and new trailing cables. Sascha Oppenhäuser: "Cat. Electrics of the crane we have received. In this way, we can provide a more economical and faster-to-implement alternative to a complete replacement of the crane."
The project is comprehensive: 200 meters of crane runway to be replaced, four trolleys for the two cranes, as well as a completely new crane bridge with a span of more than 24 meters and a new trailing cable system to be supplied and installed.
Mammoth modernization in the coil warehouse
In order to complete this mammoth task on time without disrupting production too much, the crane runway replacement and the work on the cranes themselves will take place simultaneously and be optimally coordinated. "Our teams at Konecranes and KSR plan their work steps precisely so that they don't get in each other's way at any time," says Sascha Oppenhäuser. "In this way, we ensure a smooth workflow."
Transporting the new, enormously long and very heavy crane bridge is a particular challenge here. From the special truck to the hall and up there to their final position, they transport up to four truck-mounted cranes. Sascha Oppenhäuser: "Our project management ensures that not only the bridge, but also the right experts are there on the right day to install it."For the replacement of the trolleys also on the second double-girder bridge crane of the warehouse, this is "jacked up" for a short time. The new crane runway and trolleys are more robust and designed for higher loads than the original components and are therefore future-oriented.
Modern safety features
To ensure that the modernized cranes are just as safe to work with, the experts at Konecranes also equipped them with a range cut-off system. It prevents the trolley from driving under load into a defined part of the hall – which could endanger the statics of the crane runway. For this purpose, laser distance sensors detect the position of the trolley and trigger braking when it comes close to the defined safety zone. "In addition, we have replaced the balancing crosshead on the trolley with a crosshead with an integrated duplex measurement axis. In this way, the control system reliably detects how much load is on the hook," explains Sascha Oppenhäuser. Despite the large scale of the project, Konecranes' teams rely on. KSR jointly implements the project on time. Sascha Oppenhäuser on the joint success: "We have shown that we complement each other perfectly with our colleagues from KSR, and have optimally implemented a highly complex process for our client."The modernized cranes have been efficiently and safely lifting their valuable steel load in Bönen again since the beginning of January 2021.