A bridge that connects New Hampshire and Maine may look very similar to the almost 100-year-old bridge that it replaced, but it has been equipped with some revolutionary technology. The bridge has been outfitted with an energy chain system from igus to guide the motor and fiber optic cables that aid in the raising and lowering of the span, thus improving reliability and dramatically reducing maintenance costs.
The Memorial Bridge, which was originally built in 1923, spans the Piscataqua River. The structure, which pays homage to local sailors and soldiers who fought in World War I, connects Portsmouth, N.H. and Kittery, Maine. A vertical lifting mechanism raises the bridge to allow ships to pass under it. The bridge must rise more than 131 ft at an average rate of about 3 ft/sec.
Instead of the hanging cables used in the original design, bridge builders used pre-assembled igus readychains. The cables were harnessed with connectors and fitted with energy chains, which were pre-assembled in the nearby igus factory in Rumford, R.I. and delivered as ready to install at the job site.
Engineers select flexible cables for the job
Portsmouth and igus engineers used highly flexible chainflex cables in the E4 energy chain as well as heavy-duty CFXL clamps for secure cable strain relief. Each of the installed cable types – including the CF300, CF9, and CF34 motor cables and the 4-core CFLG fibre optic cable – were extensively tested in igus’ test laboratory. The chainflex cables include an industry-best 36-month guarantee.
igus, whose headquarters are in Cologne, Germany, runs its North American operations out Providence, R.I.
The two-lane bridge carries U.S. Route 1 over Badger’s Island and is slightly more than 400 yards long. Prior to the overhaul the original Memorial Bridge was closed in 2011 after a series of emergency closures related to safety concerns. The bridge is currently the only one of the three Piscataqua River bridges with provisions for pedestrians
See the readychain systems in operation below: