The Öresund Project - suspension bridge for combined rail and road traffic

The High Bridge - project description
The 1092-metre long superstructure of the High Bridge is being fabricated at the Karlskrona shipyard. The Öresund bridge superstructure, which will be built in sections, is the largest steel project ever in the history of the yard. A total of 16000 tons of steel will be used in order to produce eight steel elements: two of 120 metres and six of 140 metres in length. The height is 11 metres and the width 31 metres. The largest part weighs about 2000 tons.

The eight sections will be transported by barge to Malmö North Harbour, where the concrete road deck will be cast on top before being lifted out to the bridge line with the Svanen crane.

The superstructure will be supported by two pairs of pylons. Each pair consists of two concrete towers, cast in-situ, with a height of 204 metres.

The High Bridge, building of the superstructure In order to build the superstructure, Karlskrona Shipyard invited several welding consumable suppliers to recommend their appropriate products for the project. Most of the welding was planned to be automatic, or semi-automatic with flux cored wire.The demands that had to be met were CVN values at - 40°C, and CTOD testing at -10°C for thicknesses above 50 mm. The base material was mainly 420 ML. As well as the mechanical properties, Karlskrona Shipyard had some additional demands on the products. User friendly and high productivity consumables were of course some of the main issues from the production side.

In order to meet these requirements Elga recommended two different wires for the production at Karlskrona Shipyard. One metal cored wire, Elgacore MXA 55T, for automatic and semi-automatic welding, and one rutile flux cored wire, Elgacore DWA 55L, for manual welding in all positions. The metal cored wire was also to be used for single sided root-runs in dip transfer when necessary.

Elga's involvement in this project has included the following items
- Recommendation of the specific consumables.
- Recommendation of welding parameters for pWPS.
- On-site survey of welding of WPAR.
- Recommendations for welding parameters for WI for different applications.
- On-site training of welders.
- On Site follow-up after production start-up.

Key Facts
Customer: The Öresund Consortium and Sundlink.
Contractor: Karlskrona Shipyard and Kockums.
Schedule for construction of the superstructure for the High Bridge: Nov.1996 - Oct. 1998
Scheduled opening of the total Sweden-Denmark link: 8th of June year 2000.
Two-level cable-stayed bridge for automobiles and trains.
Total length of the High Bridge: 1092 metres. Steel weight of superstructure: 16.000 tons.
Pylon height: 204 metres above the water.
Free height under the bridge: 57 metres.
Free span between the pylons: 490 metres.

Elgacore MXA 55T
MXA 55T is a metal cored wire for use with an Ar/Co₂ gas shield. The wire is all-positional and runs with a very stable, spatter-free arc even under dip transfer conditions at welding currents as low as 50 A. MXA 55T has excellent notch toughness properties at temperatures down to -60°C and is therefore highly suitable for offshore applications. MXA 55T is CTOD tested.

Elgacore DWA 55L
DWA 55L is a rutile flux cored designed to meet the extremely high weld integrity demands in applications such as offshore fabrication. The flux core design in combination with the 1.4% Ni alloy level produces a well balanced weld microstructure exhibiting excellent fracture toughness at temperatures down to - 60°C. The wire is suitable for use in all welding positions and exhibits very low spatter, low fume emission and easy slag removal. DWA 55L is CTOD tested.