Colas Rail is using Doosan Portable Power’s new generation of compressors to apply shotcrete to the interiors of French tunnels.
The first two new-generation Doosan 12/250 portable compressors were recently delivered to the technical team at the French company’s Les Marches offices near Chambéry. The units are Stage IIIB compliant and provide a free air delivery of 25m3/min at a working pressure of 12 bar.
The compressors are predominantly being used to spray quick-setting, dry-mix shotcrete to tunnel walls as part of renovation and refurbishment projects. The 12/250 units are installed on railway wagons and have to function in high temperatures for hours at a time. What’s more, the compressors are often pebble-dashed with concrete by the end of a shift.
Despite this tough environment, the machines are able to deliver dry air to aid effective concrete application. In order to do this, the Doosan units have to remove approximately 98% of the humidity from the compressed air before it is used for shotcreting.
“Our teams have to work in challenging conditions during operations inside tunnels, and very often have to work at night to avoid disrupting rail traffic,” explained Thierry Delaporte, technical director at Colas Rail. “Our equipment has a tough time too, so we need rugged machines. We’ve been using Doosan compressors for a number of years now and really appreciate their performance, reliability and easy maintenance.”
