Piercing mill Mannesmann

The piercing mill is a machine that can produce a hollow steel cylinder (hollow shell) starting from a filled one (solid bar). Together with the rolling mill it transforms the hollow shell into a seamless tube. The two machines where developed in Germany in 1885 by the Mannesmann brothers, who first discovered that by applying high pressure to a solid bar one could obtain a cavity all along its axis. The piercing mill exhibited at the Museum is part of the machinery that was first installed by the Mannesmann Tube Company in the early 1900s at the Dalmine (Bergamo, Italy) plant, today TenarisDalmine. Coupled with a pilger mill, it produced seamless tubes with a diameter of 47-78 mm. In operation for about thirty years, this piercing mill arrived at the Museum in 1961 accompanied by the gear housing, by the automatic hydraulic mechanical and pneumatic organs for the insertion of the bars and the exit and transportation of the hollow shells, and by the 500 HP command flywheel engine.