Technology: Special Cylinders
Hydraulic system for Bre.Be.Mi
4 special cylinders speciali of 900 ton for the lifting operations on the highway Bre.Be.Mi in Italy
The project of the new highway called Bre. Be.Mi. , connecting Brescia – Bergamo – Milano , were made a number of concrete viaducts made of a system of conjugated segments, prefabricated in the factory and lunched with wagon or crane. One of these is the viaduct called ” Adda” .
The deck of the viaduct Adda spread over two lanes of length 1,260 ml with variable spans of 45 to 90 ml conjugated segments consist of 17 ml of width , height ranging from 3.20 to 5.40 ml and depth of about 2, 70 ml .
The execution of the work has provided for the launch of the ashlar zero positioned on batteries built previously and temporarily secured to the stack through the use of vertical bars. Later they were mounted symmetrically between the precast segments solidarized by their specific adhesive post-tensioned cables and stranded . During the transitional phase between the assembly and the ashlar quoins stringing cables were solidarized bars using high strength through the use of hollow cylinders .
FPT has produced 4 special hydraulic cylinders single acting model CSE-900/120-GS TA- SP.
The cylinders are designed and manufactured single-acting , with return on load and lock nut . They have a capacity of 900 tons to 700 bar and a stroke of 120 mm, external diameter Ø555 mm and height 550 mm to closed.
The cylinders are actuated by a hydraulic pump model FPT4 – ME4 -M -100- 4U – VM2M with four independent outputs for better load management .
The hydraulic system is composed of FPT served for the positioning of Ashlar zero and its subsequent adjustments ( in transient phases is necessary to consider the different static schemes assume that the deck is not complete yet and made integral).