MACHINE ELEMENTS agreed
MACHINE ELEMENTS agreed on a timetable of 7 days. “Eventually the 7 days became just 4. Now that really is an extremely small window for a replacement job of this type,” admits Andersson. 01 Weighing more than 2,500 tonnes, the bulk carrier loading station rests on two massive slewing ring bearings Advance planning In view of this challenge in terms of time pressure, the conscientious planning and thorough preparation of the team from the SKF Solution Factory really paid off. “Right from the start we had basically been looking at all conceivable options. To that extent a lot of things had already been prepared down to the last detail. So in a sense, we just had to make our advance planning a bit leaner,” says the SKF project manager with a wry smile. Once Andersson‘s team finally began the replacement work, it became clear that their scrupulous preparatory planning had paid dividends. Both the removal of the old bearing and installation of the new one were able to proceed without any major hurdles. “By the end we required only two and a half days to complete the replacement work, so that the station was able to fully re-enter service after four days.” The short changeover time brought significant cost reductions for LKAB. “The rapid changeover meant a shorter laytime for the bulk carriers waiting in port. And, as a result, LKAB has of course saved a lot of money,” concludes Andersson. Enormous weights and forces To ensure the customer could enjoy this “monetary benefit”, the SKF team had to master an extremely complex task. Replacing the slewing ring bearing of the gigantic shiploader meant that the entire station, including its conveyor belt, had to be lifted. “We had to cast new lifting plates, for instance, and provide enormously powerful winches in order to be able to lift the station. Once the old bearing had been removed we needed a recovery vehicle to pull the bearing out of the structure. And when it came to installing the new bearing, we had to use this recovery vehicle again to position the replacement bearing correctly,” says Andersson. About Company name: SKF AB Headquarters: Gothenburg, Sweden Turnover: SEK (Swedish Kronor) 70.975 billion Employees: approx. 48,000 worldwide Products: Bearings, seals and lubrication solutions, linear motions and actuation systems, condition monitoring, test and measuring equipments, power transmission and coupling systems 02 Just two and a half days to replace the 20-year old slewing ring bearings, weighing around 6 tonnes each Quite apart from the technical challenges, Andersson‘s team also had to deal with the climatic conditions of the far north. Because the bearing was being replaced in March, the Norwegian weather could easily have led to problems. “Luckily, however, the weather gods were on our side. Let me explain the potential problem. The shiploader represents a big area in terms of resistance to wind forces, and at wind speeds of over 12 m/s – which are quite normal for these parts – it would have been impossible to replace the bearing. As it happened, just a day after we completed the work there were winter gales of that magnitude. If they had caught us in the middle of replacing the bearing, we‘d have had to interrupt the work.” The winter temperatures were another complication. “When we were carrying out the replacement work, the temperature onsite was -10 °C. As a result, the grease that 03 The slewing ring bearing replacement operation was partly down to the intervention of the Norwegian weather gods we wanted to fill the bearing with solidified. So we had to get hold of a different lubricant and managed to keep it warm using industrial fans,” says the SKF expert. Hard work brings its own reward Thanks to the successful replacement of the swivel ring bearing, LKAB continues to rely on SKF. “After we had managed to replace the rear swivel ring bearing of the shiploader in such a short time, we were entrusted also with dealing with the front one,” says Andersson. The SKF team has since successfully completed replacement of this bearing as well. Apart from that, in its mines LKAB also relies increasingly on SKF condition monitoring systems. Photographs: SKF www.skf.com MDA Technologies 5/2015 25
DRIVE TECHNOLOGY I INTERVIEW Lenze: Innovation and internationaliz At the company conference in Stuttgart, Germany, I had the opportunity to meet and interact with CEO of Lenze Group, Christian Wendler. In his presentation and later in our conversation as well, Wendler pointed out the key factors and sectors that will play an important role in the near mid-term future. The global economy grew by 3.3 % in 2014. The Eurozone GDP grew by only 0.8 % in real terms. There are uncertain prospects for growth in the machine-building industry because of volatility in the willingness to invest, which is partly a result of the sovereign debt crisis in the Eurozone, and the conflict in Ukraine. On the other hand, Germany’s exportoriented machine-building industry is profiting from positive effects in currency exchange rates, historically low interest rates, and the advantageous price levels of energy and raw materials. Industry 4.0 - the focal point of the Lenze’s R & D The desire to make the production of goods faster, more flexible, and further efficient is at the heart of R&D work today. For the machine-building industry, the central question is how a “Smartt factory” should be equipped. Christian Wendler, the CEO of Lenze group, talking at the company’s conference in Stuttgart, said “With our intelligent solutions we are supporting self-optimising machines. Our innovative product portfolio fulfils the requirements that Industry 4.0 imposes on a machine. Standardised and modular software provides more flexibility, modularity and speed. Modern concepts make it easier for machines and humans to cooperate. Open standards and interfaces ensure networking and communication. Our intelligent drives adapt flexibly to a variety of machine tasks and are easy to operate - for example, with a smartphone app.” 26 MDA Technologies 5/2015
