Keeping high-speed trains looking their best
St. Petersburg, December 2017 – High-speed trains are an important transportation alternative to air traffic. At regular speeds of 250 km/h and more, the outer skin of the trains is exposed to maximum stress. Therefore, the paint must be repaired at regular intervals. In St. Petersburg, Siemens has recently started using a Dürr combination booth with painting and drying function for the maintenance of the Russian high-speed Sapsan trains. One of the paint booth's stand-out features is its energy efficiency.
The 30-meter long booth is used for filling, sanding, painting, or drying. Dürr looked after everything from planning to commissioning including application. “The new paint booth can be used in a variety of different ways, and is equipped with application technology. It is setting new standards in the painting of multiple units and carriages, not least thanks to its low energy consumption”, says Dr. Hans Schumacher, Head of Dürr's Application Technology division, in explaining the benefits of the efficient system.
Best possible working conditions
The steel structure features internal tracks on which the carriage enters the booth, with residual space coverings used to minimize the energy consumption. These rest almost flush against the train contour at the entrance and exit to ensure better sealing of the hall. This solution reduces energy consumption and improves the working conditions in the booth.
The repair work on the trains is then started from the two mobile elevated work platforms. The scissors lifts extend two meters past the apex of the carriages and locomotives, making it easier to perform repairs on the roofs of the trains.
Dürr spray guns from the EcoGun series are used for painting. They are especially well suited for even paint application. Dürr pressure pots with compressed air stirrers ensure a continuous paint supply.
Depending on the type of damage, the damaged areas are first sanded, then filled if necessary, and finally painted and polished. The mobile elevated work platforms can travel the entire length of the hall during this process, enabling all parts of the train to be reached. Once the damage has been repaired and painted, the booth can be switched over to the dryer function. This is achieved by heating the internal space to 60 degrees.
High energy efficiency
The use of zone circuits in the Dürr combination booth enables separate and independent control of the air flow to a total of four zones. This means that while paint is being applied in the first two zones, for example, it can be drying in the last two zones, since the zones can be separated by means of a roller door in the middle of the booth.
Heat recovery rotors also ensure that the fresh air for the paint shop is preheated by the exhaust air before it is heated to the desired operating temperature (generally 20 to 22 °C) in the heating register. In drying mode, the system is operated with recirculated air in order to achieve the required drying temperature. The system automatically switches to energy-saving mode during breaks in painting lasting more than 20 minutes to prevent unnecessary energy consumption.