Hollow plunger hydraulic cylinders for the tightening of the anchor rods of the Aquitaine bridge.

The second largest French suspension bridge.
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Hollow plunger hydraulic cylinders





Hollow plunger hydraulic cylinders, manufactured by FPT – Fluid Power Technology, used for the tightening of the anchor rods of the 128 collars of the Aquitaine bridge, the second largest French suspension bridge.

In 2021, the DIR Atlantique appointed the French subsidiary of Freyssinet, a global company famous for their expertise in the construction and maintenance of bridges and cable structures, to undertake the tightening of the anchor rods of the 128 collars of the Aquitaine bridge. This operation requires the installation of scaffolding for the first collars accessible from the cycle path, and a mobile equipment attached to the carrying cable for all the others.
In June, the teams of the Freyssinet GPCM (Grands Projets, Câbles et Manutentions) agency started the works consisting in re-tensioning all 1,536 rods using specific jacks developing tension values of around 500 bars. The tension developed on each rod allows the loosening of the nut and a variable tightening but generally equivalent to 1/8 of a turn.

This operation, which must be repeated approximately every 10 years, was carried out using the FPT high pressure hollow plunger hydraulic cylinders with 80 ton @700 bars with 80 mm stroke, designed and produced on customers specifications. The work is carried out without interrupting traffic.

FPT is specialised on the engineering of hydraulic cylinders and pumps used on civil engineering sector for the construction of bridges, reinforcement and improvement of soils and repairs of structures. Hydraulic jacks with any size, force, stroke and special functions, designed and manufactured custom made are part of our production. FPT Fluid Power Technology is highly specialized in the engineering and production of new technical solutions for lifting, tensioning and bolting with an absolute quality of the products. ISO 9001: 2008 certified quality management system. Strong ability to design and manufacture custom made equipment able to respond to the most specific customer requests.