Problem
The pulley module is an equipment that can be attached to a standard 40-ton hydraulic excavator. It is designed to extract mining waste from the excavation of pits up to 65m deep. It consists of a module with winches and hose reels. This module weighs almost seven tons and is attached under the boom of the machine with a quick-change system. Furthermore, a guide roller module is installed, which is attached to the end of the dipper arm of the excavator with a quick-change system. The cables and hydraulic hoses are attached to a hydraulic clamshell bucket with spreader, which have a system for dampening the tensile forces. Four machines are currently being used on the GRAND PARIS EXPRESS construction site; the construction of a metro line on the outskirts of Paris that has to pass under existing networks and tunnels, which explains the great depths that have to be reached without any problems. Thus, a small space is necessary of the machine.
Solution
The vertical line of the centre of gravity of the winch and hose reel module runs within the area where the tracks rest on the ground, which contributes to the stability of the entire unit. Accordingly, all installed parts must withstand the heavy weight, which poses no problem for the igus® parts. With the TGP equipment (Terrain Grande Profondeur), the machine is very powerful, compact and relatively easy to transport. In terms of easy folding and a long service life, the igus® solutions were able to prove themselves against the metallic alternatives. No maintenance or regular lubrication is required. The small requirement of space of this machine, both during transport and at work, are an advantage for these construction sites in urban environments. In the transport position with the hose reels folded in, the machine is identical to the basic excavator in all three dimensions.