Valmet’s unit in Karlstad, Sweden, reaches a historic milestone with the delivery of its 700th Yankee cylinder. Designed for maximum efficiency, this drying cylinder is a key component of Metsä Tissue’s new mill – one of the world’s most advanced tissue production facilities now taking shape in Mariestad, Sweden.
Early April, Valmet in Karlstad, Sweden, waved farewell to yet another impressive drying cylinder. These massive yankees, which can weigh around 200 tonnes, typically travel across oceans and along rivers to customers worldwide, often taking months to reach their destinations. But this time, the journey is much shorter—the final stop is at Metsä Tissue in Mariestad, just across lake Vänern.
Valmet and Katrinefors Mill in Mariestad share a long history. As early as 1915, 110 years ago, the first yankee was shipped from Karlstad. When Valmet decided to invest in tissue technology in the mid-1970s, Katrinefors Mill became the site of the first Valmet machine. Now, 50 years later, the circle is complete with a groundbreaking project at the same location. The new drying cylinder is the tenth delivered to Mariestad and the 700th manufactured in total in Karlstad.
A groundbreaking tissue production facility is taking shape in Mariestad, set to be one of the most modern in the world. Metsä Tissue is making a strategic investment in the future by building an advanced tissue production line with optimized energy efficiency and minimal water consumption to reduce its climate footprint. The goal is to achieve fossil-free production by 2030.
Valmet has been entrusted with delivering a complete production line, from pulp handling to the finished consumer product. The tissue machine is developed and mainly manufactured in Karlstad. With a 5.6-meter-wide paper web and a speed of up to 2,200 meters per minute, the machine has the capacity to produce 70,000 tonnes of tissue annually. The two converting lines are supplied by Valmet’s production unit in Lucca, Italy.
A key component for energy efficiency is the large yankee cylinder. With a diameter of 6,700 mm (22 feet), a shell length of 6,260 mm, and a transport weight of approximately 206 tonnes, this is one of the heaviest yankee cylinders ever manufactured in Karlstad—and one of the largest in the world used for tissue production.
The shell surface, spanning 130 square meters, has been polished to an exact finish, free from deviations or defects, as even the slightest irregularity could risk breaking the delicate tissue layer. The yankee is classified as a pressure vessel and, when in operation, stores energy equivalent to 600 kg of TNT (trinitrotoluene) or the force of 2,500 dynamite sticks.
Valmet is responsible for the startup and commissioning of the facility, with the goal of quickly reaching an optimal production level and the highest paper quality. To support the operators in Mariestad after startup, Valmet’s experts can remotely monitor the production process through the Valmet Performance Center. From there, they can provide proactive recommendations, assist in troubleshooting, and address process-related questions.