An integrated Enerpac system was introduced to help produce large concrete blocks during the expansion of the Cartagena port in the South of Spain.
Drawing on the same high pressure (700 bar) Enerpac hydraulic technology available throughout Australia and New Zealand, the system went into service to lift and lower a construction umbrella holding concrete block construction formers.
Cartagena is expanding its capacity, and additional jetties are being built to further protect the harbor from the sea. According to Enerpac, the construction process for the jetties is based on that of concrete blocks. Not the average size concrete block, but the large blocks built are 70 x35 x 35 meters.
Just as major port and infrastructure developments under way in Australasia are demanding advanced engineering techniques for safety and efficiency, the Cartagena project demanded a solution tailored to local conditions.
NECSO, main contractor for this project, purpose-built a large catamaran style concrete block builder for the project. The KUGIRA is capable of building a super-size block every seven days. On one of the existing piers of the Cartagena port, a sizable concrete factory serves the enormous catamaran in the harbor that carries the actual concrete block builder.
The KUGIRA, uses a sophisticated hydraulic integrated system to lift and lower the so-called construction umbrella that holds the block construction formers. On both sides of the catamaran, 15 sets of stage-lifting hydraulic units operated by three high-flow power sources and controlled by a synchronized PLC system operate the 35-meters-wide and 70-meters-long umbrella. The umbrella is shaped to form the blocks, including the internal cells for stiffness and valves for control during the sinking process.
Because of the size of the concrete block (and thus the umbrella), the risk of twisting and therefore locking the umbrella between both catamaran walls could have been a serious threat to the process. For that reason, a fully PLC controlled synchronized hydraulic integrated system was designed by Enerpac’s European Construction Center of Excellence. Technical director Jesus Gonzalez based the synchronized design upon a hydraulic climbing stage-lifting technology (a technology also available throughout Australasia).
Along both sides of the catamaran huge but lightweight constructions hold the climbing stage lifting steel notched plates, while the climbing stage lifting hydraulic units are fastened to the umbrella deck. Each unit incorporates an advanced ENERPAC hydraulic system including stroke and proximity sensoring
All 30 climbing units comprise two long-stroke hydraulic double-acting cylinders of 70 tons capacity and two double acting hydraulic locking cylinders of 20 tons capacity. The long-stroke cylinders, used for the actual lifting and lowering process, include a magnetic stroke sensoring system, which communicates the plunger’s position via a local manifold and valving unit to the central PLC-system.
The locking cylinders also include stroke sensors that signal their position to the PLC-system where all data is processed and communicated back to the pumps and 2/2-way valves that control all cylinders (120 in total) in all 30 climbing units.
The locking cylinders are used to fix the climbing units during the climbing process. The main PLC-system is operated via a touch screen with a graphical user interface, continuously showing the actual stage of the process, including all parameters. Overall lifting and lowing accuracy of the entire system is better than plus/minus 1 mm.
The size of the port project and future upcoming projects of this type of port and jetty building was the main reason for NECSO to design the ship with maximum flexibility. Not only concrete blocks of 35 x 35 x 70 meters can be built, but also several other sizes. One option is to build 2 blocks simultaneously of 35 x 35 x 34 meter each, while another configuration allows the construction of one block of 35 x 35 x 34 and two blocks of 35 x 35 x 16 meter simultaneously. Consequently the ENERPAC hydraulic system is designed to deal with all these different configurations.
Advanced hydraulic systems, including stage lift systems, feature in Enerpac’s new E325a Australasian catalogue. The catalogue, introduced this year, includes synchronous lifting systems that one person can operate from up to a kilometre away to lift giant weights (including bridges, turbines, draglines and drilling platforms).
Enerpac offers Australasia’s big selection of (700 bar) cylinders, in hundreds of models with capacities from 5-1000 tonnes for compact high-pressure power in lifting, pushing, pulling, bending and holding applications.