Alping hand21 September 2018
Stahl CraneSystems supplied chain hoists used in a tunnelling project in Austria, working with French bespoke lifting solution developer Acimex.
Acimex specialises in the transportation of objects weighing several tons, using vacuum lifters, or hydraulic and mechanical grabs Germany’s Stahl CraneSystems has worked with the company regularly to equip these attachments with lifting systems, supplying the construction, metallurgy, aviation and energy industries.
For a tunnelling project in Semmering, Austria—where a 27.3km railway tunnel is being constructed between Gloggnitz and Mürzzuschlag in the northern Alps, due to open in 2026—Acimex developed segment trolleys and segment erectors to handle the individual pre-cast elements at the tunnel construction site.
The segment trolley, fitted with a vacuum lifter, grips and lifts the segments from the service train and transports them deeper inside the tunnel. The segments are then picked up by the segment erectors using an air vacuum, and placed in their final position.
The Acimex segment erector is fitted with two lateral rubber suction cups fastened under the chassis and a central vacuum pump, and can turn the elements in X, Y and Z-direction by up to 360°.
The parts weigh up to 20t each and need to be positioned with an accuracy of within 5°.
The project uses three electric chain hoists from Stahl CraneSystems to adjust the pre-cast elements.
Also supplied were SHF 50 20-40 wire rope hoists with 1/1 reeving and a rope drum length of 2. These hoists required an above-average lifting speed, which was achieved by using a hoist controller with frequency inverter and closed-loop encoder.
The closed-loop encoder, combined with the software used, enables the operator to control the actual speed of the hoist relative to the set-up speed and to adjust the setting data if required, allowing lifting speeds of 7–12m a minute.