Messer News
The Viaduct of Millau, France - Technical Masterpiece

The highest Freeway bridge in the world, the Viaduct of Millau, has been officially opened for traffic by the French President on 16th December 2004.
Millau Viaduct

The various bridge sections were pre-fabricated from individual steel plates in their factory at Lauterbourg, France (near Strassburg).
With a height of 345 m, it is 20 m higher than the Eiffel Tower. Despite its length of 2.460 m and 36.000 tonnes of steel incorporated in it, the bridge was completed in a record time of only 3 years by the company Eiffel.

Important criteria for the success of the total project were:
  • High fabrication speeds
  • Tolerance for the weld seams (bevel and X weld preparation cuts) less than 1 mm. (This was the prerequisite to be able to fabricate the individual parts into sections using welding robots without any problems,.)
  • Permanent marking of the individual components with alpha-numerical information about the part number, position where it was to be used etc.
These requirements could all be met with the use of a cutting machine OmniMat L specially designed by the company Messer Cutting Systems, Groß-Umstadt, for this application and equipped with a 400 A Oxygen plasma unit and a needle marking system. An integrated X Y coordinate slide incorporated into the machine enabled the initially specified marking speed to be exceeded by a factor of 4.

A postprocessor developed by Messer Cutting Systems converted the geometry data coming from a CAD system completely automatically into the technologically correct CNC data needed to perform the weld preparations.

A CNC integrated compensation software automatically corrected for the plate expansion due to temperature for a reference temperature of 15 °C. This ensured that the cut parts for the section were all of the same size regardless of whether they were cut at-5°C in Winter or at +30°C in summer.