POMA, based near Grenoble in France have been pioneers and innovators in ropeway transportation systems since 1936, creating solutions in naturally challenging environments. POMA where awarded the contract to design and install a J-bar Ski Lift at the Bulgarian resort of Vitosha with a height of 950m and a transit time of approx. 5:50 minutes with a capacity of 900 people per hour. The question came about how best to secure the towers to the foundations to ensure a high integrity fixing of the anchorage bolts.
Bolt tensioning was the chosen method with HYDROCAM® bolt tensioners selected:
8 off HTC-R designed hydraulic bolt tensioners the most powerful tensioner in the standard range, can apply very high traction loads. The brace and body are monolithic reducing the outer dia. of the unit. The unit also comes with automatic piston return and with few parts is easy to use, its also well suited for simultaneous tightening.
Due to the fact that the bolts are set in concrete and not always perpendicular a spherical skirt was supplied to accommodate the misalignment