The Variolock fully hydraulic quick coupler system from LehnhoffPublished 23/9, 2019 at 12:11
The fully hydraulic quick coupler system Variolock, made by Lehnhoff, has recently proven itself on the demolition of three railway bridges on a project located close to the North Sea. Using the system, Rostock company Abbruch Büchert GmbH, was able to facilitate the swift, easy, and safe exchange of attachments that ensured that the company kept to its gruelling schedule.
In North Frisia, close to Bredtstedt and Breklum, three railway bridges required demolition due to being ‘worn out’, with the Deutsch Bahn (German Railway Company) deciding to replace them with new ones. The contract for the dismantling of the bridges was given to Abbruch Büchert GmbH, with the project set to be completed within 24h. In total, twelve excavators were used, with the fully hydraulic Variolock VL 250-2 quick coupler system from Lehnhoff ensuring that attachments could be changed effortlessly and swiftly.
“Certainly, no spectacular objects but a critical time frame for sure,” so said Martin Büchert, chief executive of Abbruch Brüchert GmbH. His team had only 24h to complete the job before the trains to Sylt started moving again, meaning that exact planning and precisely timed working steps were required. Any delays or interruptions meant that the Variolock VL 250-2 system was essential to the successful completion of the project, with attachment changes kept to the absolute minimum.
Work began at 3am, starting with the biggest of the three bridges to be demolished which was situated in the village Bredstedt. The demolition site was illuminated by floodlights, with the bridge demolition requiring a 1,500m3 embankment and 260m3 of Ferro concrete needing to be removed. Two crawler excavators with 30t and 26t operating weights respectively were put to work using trench clearing buckets on the embankment. On the other side, another 30t machine worked in parallel. The excavation work ran smoothly thanks to the tilt-able buckets, with the embankment being removed in around 1h. Following this, the bridge could then be demolished, with the buckets being exchanged for hydraulic demolition hammers, the biggest one weighting 4.1t. The use of the Variolock system enabled a swift, uncomplicated and safe change of attachments within minutes.
After a short while, debris and rubble was piling up high. To keep things organised, one of the excavators exchanged the hammer for a sorting grab to tidy up the demolition site, while the others continued to work on the bridge. Three dumpers were filled up before the sorting grab was once again exchanged for a hammer. The hammers continued their work without any delay, thanks to the fully hydraulic quick coupler unit by Lehnhoff. This meant that there were no breaks due to manual coupling of hydraulic hoses, with the entire exchange being undertaken from within the cabin.
The breakdown of a railway crane used by another company on the demolition project led to a 2h delay, jeopardising the tight schedule of the project. The use of the quick couplers however meant that the project was completed 5h ahead of schedule. Martin Büchert stated: “I can only bow to the inventor of this system. Everyone who has tried this system once will never want to work without it.” For his company, fully hydraulic quick couplers can save up to 30% of working time due to the reliability and speed of the system, meaning that Bücher was able to draw up the tight 24h schedule. “In any other case, we most definitely would have needed more time,” he adds.
Abbruch Büchert GmbH as a company is not limited to earth works, demolition, dismantling, and disposal, as it also undertakes the construction of protective scaffolds and asbestos abatement. The company has been working with Lehnhoff since the early 90s, and today this is a solid partnership, which has proven itself once again on this special project. “The quick coupler system Variolock VL 250-2 has contributed significantly to a successful completion,” says Büchert.