Footbridges built in Lean Duplex

On commission from Equinor, large footbridges were constructed in Lean Duplex

Bridges in Lean Duplex being transported to their location at Mongstad

In the fall of 2020, our partner, Fabtech, was commissioned by Equinor to build footbridges to replace the existing footbridges on the Mongstad facility. The pre-existing bridges were constructed in painted carbon steel.

We wanted to challenge the existing solution and replace carbon steel with Lean Duplex as a more sustainable and durable solution. With the use of Lean Duplex it is possible to have a lighter structure, less maintenance, and reduce the CO2 footprint.

Structural hollow sections manufactured by Stalatube

With good assistance from our technical team of metallurgists and the availability of material, the change from carbon steel to Lean Duplex was a fact. The selected material grade was Lean Duplex acc. to EN 1.4362 / UNS S32304 in accordance to NORSOK M:120 – MDS YD37.

We supplied over 2000 meters of structural hollow sections in addition to plates and hot rolled angle bars. All the items were provided in Lean Duplex and delivered from our site at Kløfta in Norway.

Advantages of Lean Duplex:

  • High strength
  • Good corrosion resistance
  • More predictable price level
  • Good fatigue strength
  • More than 30 % weight saving on most applications
  • Low life cycle cost due to no need of regular painting
  • 100 % recyclable and made from more than 85 % recycled material

Although the bridges were built in 2021, the installation did not occur before June 2022 due to rough weather conditions.

Published: 18 Oct 22

By: Elisabeth Kruiderink

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