Sometimes it just all comes together: the largest manhole covers in terms of area that we have developed and installed to date are also a prime example of the expertise available at ACO Passavant Detego. The customer was the Luxembourg tramway company Luxtram, who had some additional requirements for the oversized floor access hatches they were looking for. The deadline: tight. And it all got even tighter, back in the spring of 2020 ...
Luxembourg aims to reduce the number of cars in the city centre. In order to achieve this, public transport has been free for everyone since February 2020. In addition, the Grand Duchy is investing 2 billion euros in public transport. These include electrically powered trams that run without overhead wires. These trams charge their batteries within seconds while at stops. This requires powerful transformers, which need to be buried under the ground along with their associated infrastructure. We were asked to develop the transformer covers. The design of the covers was supposed to blend in with the surrounding architecture.
Large transformer covers with additional requirements.
It was clear that special solutions had to be developed for these manhole covers. Manhole hatches in the required sizes are not available in any standard range. A total of five special shaft covers were required, two of which were of the same design: the largest floor cover with an area of 3 x 19 m at the main station, the second largest at Place des Metz, a cover at Place de Paris and two identical ones at the Hamilius and Place de Paris stops.
Apart from the sheer size, the additional requirements placed on the manhole covers were also intriguing. They also needed to be impermeable to water, thermally insulated and able to withstand being driven over by lorries. They should have an automatic opening due to the frequent foot traffic. Furthermore, it was the architect's wish to have covers that were as inconspicuous as possible. There was also to be as little metal visible on the surface as possible and the hatches should be able to accommodate paving.
After our offer was submitted in the spring of 2019, the contract was awarded in October of the same year and with it the time for construction. Construction was scheduled to begin in April 2020 and to be completed in December 2020. Of course, in the construction industry we are well aware that deadlines can be tight. What nobody could have expected, however, was the Corona pandemic and the accompanying restrictions on freedom of movement and the movement of goods.
Special manhole covers and two-shift operation.
The fact that we have managed to get through this first Corona phase well is largely due to the good cooperation with our clients and the tremendous dedication of our team. Complex challenges like the Luxtram project always spur us on to achieve our best. Working in two shifts, we were able not only to develop the perfect solution for Luxtram, but also to satisfy all of our other customers in this turbulent year.
Countless individual parts were welded, edged and laser-cut for the manhole covers in Luxembourg. For a project of this size, we of course carried out the installation on site ourselves. Once again, the outstanding cooperation with the other contractors was remarkable: no sooner had we installed and approved the covers than the paving of the covers began, allowing them to blend into the anthracite-coloured paving in a way that was barely noticeable.
Punctual completion and successful installation.
Completing and installing our manhole covers on time is, of course, always one of the most important goals. This time we had a special celebration, as the handover could take place as planned in December 2020, in time for the opening of the tram line just before Christmas.
The special size of the construction also brings with it special requirements for the materials. As was to be expected, our factory can withstand these stresses in everyday operation. This is confirmed by the servicing we regularly carry out on the manhole covers in Luxembourg.
The result can be clearly seen as there is so little to actually see. As requested by the client, only a small amount of metal is visible on the surface. By using natural stone, we have met the special requirements for design and visual appearance of the surface. The integration into the local architecture has been particularly successful at Place de Metz, where the second largest shaft cover is located.