Marraffa’s first bridge job using Enerpac jack-up

The Enerpac JS-250 jack-up system and its stack of barrels supporting the bridge deck before temporarily resting it on supports made from stacks of Enerpac barrels. Photo: Marraffa SRL

Heavy lift and specialized transport company Marraffa in Italy completed a railway bridge installation with the help of heavy lift hydraulic systems.

The job was a steel bridge on the new Napoli–Bari high speed and high capacity railway line (HS/HC) in the province of Benevento, north of Naples, in the south of the country.

The 65 metre long bridge weighed more than 600 tonnes. Marraffa’s job was to lift it from beside the railway line and move it sideways into position on its piers. The bridge was already spanning the 30 metre wide river below.

First of the two hydraulic lifting systems deployed was a new Enerpac JS-250 jack-up. The JS-Series jack-up system uses towers positioned under each corner of a load. Each tower has four hydraulic cylinders to lift the load while steel barrels are added and stacked in underneath to support it.

How it works

As the load is lifted, in increments according to the stroke of the hydraulic cylinders, the support barrels are inserted using a telehandler and an automated system to form the lifting towers. One operator can manage the operation because the jacks are synchronised to lift evenly and maintain the balance of the load.

With two Enerpac JS-250 towers at each end of the bridge they lifted it from its supports to a height of 4 metres and placed it temporarily on JS-250 barrels, six-high. The bridge was already spanning the river so an hydraulic gantry crane system was then positioned to lift and move the deck sideways over its concrete piers.

“The width of the river meant this would have been a more challenging project using cranes. Using the Enerpac JS-250 ensured the bridge deck remained level throughout, making the final installation with the gantry crane easier,” said Michele Marraffa, CEO.

In addition to the JS-250, Marraffa completed its first bridge project, between Amorosi and Melizzano in southern Italy, with the help of an EZ Lifter hydraulic telescopic gantry lifting system from Riggers Manufacturing. Photo: Marraffa SRL

For the second part of the operation, a 15 metre sideways shift, Marraffa used its EZ Lifter EZ600-40 hydraulic telescopic lifting gantry system from Riggers Manufacturing in the USA. On two legs it lifts 600 tonnes and that capacity is doubled to 1,200 tonnes with four legs. Each leg consists of four hydraulic lifting cylinders and maximum height of lift is 12 metres.

Two legs were used under each end of the bridge, mounted on a steel track, and synchronised electronically.