Dredging contractor Co.Ed.Mar from Chioggia is working at the Port of Vado Ligure in Italy to expand capacity with a new terminal and deepened waterway. With naturally deep harbor (more than 22 meters or 72 feet), work is ongoing to build a new deep-sea container terminal. The self-propelled barge Wise, equipped with a Liebherr duty cycle crawler crane type HS 8130 HN with a hydraulic clamshell bucket is dredging sediment at the mouth of the port. The new terminal is expected to open by the end of 2018.
The Port of Vado Ligure in northern Italy is one of the major hubs for ferry services to Corsica and Sardinia. The port authority wants to accommodate more and larger vessels, deepening the port area between 11 to 14 meters (36 to 46 feet).
The contractor is achieving quick cycle times (45 seconds) to dredge material from the seabed and less to unload the vessel with an average turnover of approximately 400 cubic meters (523 cubic yards) per hour. Liebherr said the 6-cubic-meter (7.8-cubic-yards), mid-sized bucket allows for quicker movement with the crane and a longer outreach. “We can manipulate the bucket faster and swifter due to the lighter weight,” Gregor Griesser of Liebherr-Werk Nanzing GmbH said.
The clamshell bucket has hydraulic activation, and the shells are opened and closed by hydraulic cylinders. “The oil pressure is supplied by the machine and routed via a hydraulic line from the crane to the bucket,” Griesser said. It has a maximum water depth of 40 meters (72 feet). Outreach is variable, up to approximately 20 meters (66 feet).
The hydraulic bucket has more closing force and higher bucket volume, over mechanical cable buckets, which need one cable to open and close the bucket, so they have less overall capacity.
With a total weight of 116 tons, the machine can quickly reposition and work in different areas. The total operating weight includes the basic machine with HD undercarriage, 2 main winches including wire ropes (90 meters, 295 feet), and 14-meter (326-foot) main boom with an A-frame 7-meter (23-foot) boom foot and 7-meter (23-foot) boom head, 29-ton basic counterweight, 1000 mm grousers and 50-ton hook block. The weight of the lifting device (hoist ropes, hook block, shackle, etc.) must be deducted from the gross lifting capacity to obtain a net lifting value.