Largest Bolt Tensioner built by SCHAAFsgeissler
In February, SCHAAF received the order from a German press manufacturer to build the so far largest Bolt Tensioner with a thread size of NIE770x55. The pretensioning force, which can be achieved with this tool, is up to date unknown 90,000 kN. The weight of the tool itself is 13,600 kg and has a size of Ø 1800 mm x 1400 mm.
This tensioning tool is used for pretensioning 8 main anchors of the biggest drop forging press ever built in Germany. The machine, producing aeroplane parts, develops an unbelievable pressure of 50,000 tonnes. In order to control all this, the huge dimensions and forces are necessary.
The drop forging press shall press aeroplane parts in China in the future. Since the load on the material in aircraft construction becomes heavier these days, the requirements to the substance material becomes greater as well. Thus, you need machines with increasing power. Concerning this fact, even larger tools are planned already.
The complete delivery volume includes, besides the tool for the main anchors, numerous smaller tensioning devices, since all essential bolts are hydraulically tensioned by SCHAAF tools. Just as the huge machine, the „little“ sister of it with a total power of 12,000 tonnes is tensioned with SCHAAF equipment.