The Nynäs AB oil refinery had a worn-out pipe bridge that needed to be replaced. However, there was cabling in the existing pipe bridge that could not be disconnected under any circumstances.
- Installing the new pipe bridge without disconnecting the cabling was a real challenge and perhaps not something that everyone would attempt. But with smart solutions and flexible products, most things can be done, says project manager Andreas Gidlund.
The existing pipe bridge was old and largely rusted, and needed to be replaced with a galvanised pipe bridge in truss construction with a higher corrosion class. A particular challenge in this project was that the pipe bridge contained important electrical cabling and overhead lines, including for the operation of a lab. Therefore, the cabling could not be taken out of service under any circumstances.
- "It was a special solution to get everything over to the new trusses. A unique job that may not be obvious to everyone," says Andreas Gidlund, project manager at Scanmast.
It was also desirable to minimise excavation on site. Therefore, the project started with the construction of customised foundations. Thanks to the Scanmast truss construction being much lighter than a tube jetty in beam system, much less earthwork is required for the foundations.
- In that sense, our pipe bridges are very good. They carry a lot but weigh significantly less than beam systems. They also do not need to be welded in place or painted to protect against rust. Less steel is used for our tubular piers, which is better from an environmental point of view as they have a lower carbon footprint," explains Andreas Gidlund.
Flexible solutions for demanding environments
The project in Nynäshamn started with drawings and careful preparations. Scanmast has calculated a number of different solutions. We looked at the actual structure of the pipe bridge, but also at how the cable would be lifted over in the best way. The environment at the refinery is special in many ways, with a switchgear in the area and work going on around the clock, there is a lot to take into account. Not least in terms of safety.
- The refinery operates around the clock so there is always work going on and traffic travelling, which we have to expect. Many different cultures and languages are in the same place, so all communication on the project has been in English and needs to be extra clear for everyone. In addition, regular gas tests are carried out to avoid leaks and the like, which mean that work sites cannot be left for very long at a time. It takes a lot of planning to implement a project like this. But it has been a lot of fun! Nynäs AB was very pleased with the result and we already have more projects in the pipeline together," says Andreas Gidlund.
The 60 metre long new pipe jetty was integrated on site. While the old structure was dismantled piece by piece, the existing pipes were transferred to the new jetty. The installation and delivery have gone according to plan, although the team encountered an additional challenge. A cable that was expected to be out of service would still be there, which meant that the pipe bridge had to be adapted during assembly.
- That's one of the biggest advantages of our pipe docks, we can be very flexible. In this case, there was no problem with the capacity of the dock, thanks to the fact that we have a lot of special brackets we could review and adjust. It's a great feeling when something that could have been a problem is solved quickly and easily with a few smart solutions.