SSAB Weathering steel and domestic supply chain show their strengths

In winter 2025, SSAB supplied weather-resistant steel poles for Vaasan Sähköverkko Oy’s new 110-kilovolt ring line. The project’s main contractor is ENP Power Oy, which specializes in power line and electrical grid construction.

“The 11.5-kilometer Träskböle–Norrskogen power line enables maintenance during fault situations without disrupting electricity transmission in the area,” says Daniel Yrjas, Project Manager at Vaasan Sähköverkko, describing the project, which supports security of supply in the Närpiö region.

The domestic origin of the product and environmental considerations had a decisive impact on the grid company’s choice of material. The project’s tight schedule also supported the decision. Part of the power line was built across agricultural fields, where the work needed to be completed during a single winter. This prevents disruption to farming, and frozen ground is best able to support heavy machinery.

“The original plans were to order standard galvanized poles. The delivery time from China would have been at least six months, and any possible changes to the plans would have extended the schedule even further,” says Marko Elorinne, CEO of ENP Power and site manager for the project.

ENP began looking for a solution together with SSAB. However, changing the material to weather-resistant steel still required approval from the client.

“A new product naturally requires consideration first. The discussions with SSAB’s experts were convincing, and the price was also competitive. The product’s domestic origin made the choice easier, and once environmental aspects were also taken into account, the decision was clear,” Yrjas says.

According to Markus Komulainen, Segment and Applications Manager at SSAB, the properties of weathering steel are based on the composition of the material.

“During manufacturing, elements such as copper and chromium are added to the steel. As a result, a dense patina layer forms on the surface of the steel, protecting it against corrosion. The surface can even repair itself if it is damaged,” Komulainen explains.

According to Yrjas, the brown, patinated surface of the poles also blends well into the forest landscape.

Together with its domestic supply chain, SSAB delivered around 40 weathering steel poles to the project. According to Jari Kallatsa, Account Manager at SSAB Europe responsible for tube sales, and ENP’s Elorinne, the process was very fast and flexible. Due to the new material, the poles were still being designed in close cooperation in October.

“During the design phase, we held a joint meeting once a week, where we always received quick and expert answers to our questions. Changes were also handled flexibly,” Elorinne says.

The first poles were ready at the end of November and the last ones in December.

“The steel coils and plates were manufactured at SSAB’s Raahe mill, the tubes at the Pulkkila mill, and the cold-formed profiles at the Toijala mill. Plate parts were cut at Tibnor Oy in Seinäjoki, and the welding of the components was completed by Ukko Steka in Lievestuore,” Kallatsa says.

The components were delivered directly near the installation sites, allowing the poles to be assembled on site with bolts and without welding.

The contractor believes that the importance of a domestic supply chain and security of supply will continue to grow in the future.

“Sea freight and long international supply chains have proven vulnerable. A domestic supply chain and a reliable supplier bring an entirely different level of certainty to project management,” says Elorinne of ENP Power.