Sandvik has recently exchanged half of the bolts installed in the historic Vasa ship during the 1960s with specially designed, high-alloy bolts. Thanks to this, Vasa ship is now both lighter and more stable. The weight savings is a whole five tons â”; about the same as if a full-grown elephant had escaped from the ship.
The cooperation between the Vasa Museum and Sandvik began in 2011, and together they developed the solution with specially designed, high-alloy bolts to replace the old, 1960s bolts, as well as tested them on the ship. Thanks to the boltsâ unique design and material, the ship is now more stable and five tons lighter â”; about the same as a full-grown elephant.
The new bolts are made of Sandvik SAF 2707 HDâ¢ and Sandvik SAF 2507®, also used in the most demanding environments in the oil and gas industry. The bolts are a combination of advanced, duplex stainless steel with dual properties: very high corrosion resistance and exceptional strength that can support the weight of Vasaâs 900-ton hull.
âThe bolt construction also gives the advantage of being able to adjust the pressure with which each bolt is fastened in the hull, allowing for precise adjustments according to the ship’s movements. Once all the bolts are changed, it will be at least 150 years before the next bolt replacement,â? says Jan Haraldsson, director of development for products and processes in steel for machining at Sandvik.