WEPA chose Toscotec for 7 custom-made hood and air system rebuilds on a turnkey basis
Since 2006, German tissue manufacturer WEPA Group has chosen Toscotec for all its hood rebuilds at various paper mills in Germany and Italy.
These projects were all turnkey operations, where Toscotec supplied the complete package for the rebuild, from its engineering design, to the components supply, down to onsite dismantling operations, erection, commissioning and start-up. For these rebuilds, Toscotec developed a custom-made design of its hoods aimed to increase production and reduce energy consumption to a minimum; it engineered the nozzle boxes and customized the air system according to WEPA’s requirements, in order to achieve top operation flexibility in cross direction moisture control and better machine runnability. Overall, Toscotec supplied other hood and air systems to WEPA in Germany, France and Poland as part of the supply of new tissue lines. The following three projects are a selection of the rebuilds carried out from 2006 to 2019.
In 2006, WEPA Marsberg-Giershagen mill in Germany invested in the rebuild of the drying section of its PM5 and selected Toscotec for the supply of high-temperature hoods and its Steel Yankee Dryer TT SYD-15FT. WEPA believed in this new technology at a time when Toscotec had only manufactured a few TT SYD, and its innovative steel design had only just been introduced into what was a cast iron-dominated tissue market back then. Thirteen years later, WEPA has successfully installed another 6 TT SYDs and Toscotec has developed and implemented three successive product generations and sold over 220 steel Yankees worldwide, including 5,600 mm width and 22 ft diameter TT SYDs. WEPA’s foresight was proved right, for steel Yankees are now recognized as the new technological standard in the tissue industry at a global level.
The gas-fired hoods supplied to WEPA Marsberg-Giershagen in 2006 operate at 600-650°C and are equipped with low emission burners running on high-temperature combustion air. The energy necessary to heat up the combustion air is recovered from the air system itself through the use of heat exchangers. As a result, the advantage of low emission burners is twofold: one is the reduction of air pollutants such as nitrogen oxides (NOx) and carbon oxide (CO), and the second is cutting the overall gas consumption.
WEPA Italia Cassino PM13 drying section rebuild
In 2013, Toscotec supplied a hood rebuild to WEPA Italia Cassino in southern Italy. The German Group confirmed the Italian supplier as the turnkey supplier of its second hood rebuild based on the advantages of Toscotec’s technical proposal. Firstly, the project was completed according to schedule, in a record time of only 6 months from contract signature to start-up. Secondly, the engineering design was custom-made based not only on the machine specifications, but also on the installation logistics, in order to avoid opening up the roof of the machine building and renting external crane equipment. Toscotec designed and manufactured these double-width hoods in separate modules and consequently achieved a significant reduction of the installation time and costs. According to WEPA’s needs, in order to reduce machine down time and speed up the mill’s administrative procedures, Toscotec realized a particular layout where the air system was installed outside the building. In 2016, Toscotec also installed a TT SYD of 18ft diameter and 5,890 mm face length on the same machine.
WEPA Leuna PM10 hood rebuild in 2019
For WEPA Leuna mill in Germany, Toscotec supplied the turnkey rebuild of PM10 hoods. As with WEPA Cassino, the Italian manufacturer was asked to factor in the installation logistics while developing the custom-made design of PM10 5,600 mm web width hoods. The advantage was that the hoods were carried into the machine building through its regular entrance and lifted using the building cranes. This reduced time and cost, as it avoided work on the roof and rental of external cranes. Toscotec completed the project on schedule within 7 days of machine down time, during which it performed the dismantling of the old parts, erection of the new ones, commissioning, and start-up. Achieving this required precise planning and the onsite assembly of key components before shutdown. Mr. Lars-Helge Peters, WEPA Leuna Mill Manager, said: “Inside the building we had to do a big crane job with evident space restraints, but Toscotec handled it very well. The start-up was perfectly on schedule, on Monday April 8th at 7 am. During the six months after the rebuild, we achieved two positive results: the first is a 3-5% reduction of PM10 overall energy consumption (gas and electrical power) and the second is the improvement of the moisture profile across all grades, from kitchen towel to toilet paper. Also, on this new configuration, compared with the old hoods, we observed an increased stability of the hood section and better runnability.”
Successful outcome across 7 projects
The results of 7 hood rebuilding projects over 13 years have been consistently a reduction of gas and power consumption higher than the contract guarantees and a significant increase in the run-ability of the machine, both in terms of overall efficiency and cross direction moisture profile. Since their first drying section rebuild of 2006, WEPA and Toscotec began a fruitful cooperation that not only led to the successful completion of 7 hood rebuilds, but also to five complete tissue lines, three of which were turnkey supplies.