Only with this angled attachment was it possible for the cranes to swing their lattice mast below an interfering edge of the building and lowered the hook block from above through the car slings for the counterweights. Each hoist raised two ballast blocks weighing a total of 89 tonnes to a height of around 40 metres into the pre-assembled frames and then attached to the lift's steel cables which are as thick as a person's arm. The car slings later surround the entire weights in the various gaps to act as safety devices. In the event of a cable tearing, the released concrete block would be held by the cables around the other weights.
The two crawler cranes and the installation teams always worked at the same level on both edges of the new boat lift. For static reasons the counterweights had to be installed almost synchronously. The boat trough on which large tensile forces act through the steel cables must not be exposed to one-sided loads for long periods of time. There are also thousands of sandbags in the belly of the 115 metre trough. The more counterweights were attached, the more of these big bags were required to keep the trough on the ground.
It was not an easy task for Sarens to plan two suitable, identical crawler cranes for this job. The company has eight LR 1600/2 cranes in its fleet "Four of them are in Canada, one each in Saudi Arabia and Kazakhstan and we only have two in Europe. So we had to have these two cranes at the same time on the site in Niederfinow", explained Hendrik Sanders, Equipment Engineer and crawler crane expert at Sarens. "That became a major headache for our schedulers."
