The invention refers to a dredge for the extraction and cleaning of sediments in bays, port accesses, navigable channels, docks, streams, lakes or reservoirs, equipped with the means for excavation, dragging, bottom removal and the means to regulate and support, with a driving force (of such dredger), that is actuated from land and not from a ship on the sea surface (water), which usually occurs with existing dredgers according to the state of the art.
Dredgers are the machines or ships used for dredge operations. Dredging is the operation of excavating and cleaning sediments in waterways, lakes, bays, port accesses, etc, to increase the tonnage of vessels and their load capacity. The depth of a navigable cannel or river determines the size of the vessels that can navigate them.
Rivers and tides drag sediments that are deposited at the bottom and calmer bays or waterways where the ports are built, decreasing their depth and therefore the tonnage of the vessels that access them. In order to improve the capacity of water transportation, when ports are embarked they must be dredged to increase or recover their original capacity. On the other hand, increasing the draft in these areas not only facilitates maritime traffic but it also decreases risk for the vessels, avoiding grounding.
Different types of dredges are used depending on the material at the bottom to be dredged.
Dredging operations have a significant potential environmental impact: at least the substantial alteration of the bottom and the mud removed generates too many suspended solids which affects a large radius surrounding the site. These environmental impacts should be evaluated properly and in a timely manner so as to consider the possible means of mitigating them.
Among different types of dredgers, the following are included:
a) Clamshell Dredgers.
These operate using a mobile arm that extracts material from the bottom.
b) Bucket Dredgers:
Small buckets extract the sediments, c) Hydraulic suction dredgers:
These are used on soft land and are generally coupled to floating tubing through which the material is moved to the shore.
With regards to the state of the art for dredgers in general, we can cite patent ES 471,035, which refers to a dredger that has a floating body, an arm that extends forward and at its front end it has a dispersing tool, with such mounted arm pivoting at its back end over the floating body, with the purpose of being able to adopt an operating position that is more or less submerged and with an upward resting position, including means of suspending the arm to regulate its position, where the arm is equipped in two sections, the first being mounted as pivoting on its back end around a horizontal axle over the front end of this first section of the arm, while the second section of the arm is mounted to be mobile on that platform, characterized because, on one hand, there are means provided to keep the platform horizontal and on the other hand, the mobile assembly of the second part of the arm on such platform consists of a pivoting assembly around a vertical axle.
Another patent invention, is ES 2,099,244, which refers to a dredger which is equipped with at least one tube (5) adjusted at a random angle, which has a scarifier belt (6) for the excavation of deposits and other light sediments, characterized because the scarifier belt (6) extends to the lowest part of the tube (5), the part of which comes out of the tube (5) and ends in a scarifier blade (9″) so that the deposits and other light sediments may be transported along such tube (5).
In order to reduce operating costs a large part of the site and specifically most of the driving force to operate the dredger is installed on land and not at sea (water) as is usually done in current dredgers in the state of the art.
To improve the ability to regulate the penetration of the shovel that corresponds to the dredger that is the object of the invention, it is equipped with wide skids so that they do not sink in soft material, and with a regulating mechanism allow a larger or smaller angle of attacking the sediments at the bottom.
The skids are also equipped with air chambers similar to those of submarines, which allow to provide an exact setting of the pressure desired on the sediments.
These air chambers also allow that only a minimum amount of driving force is used to move the dredger shovel, without sediments, either when moving backward or when transporting.
To alleviate suspended solids, which produce a large impact on the macro and microscopic wildlife in a wide radius around the site, increased by current and/or tide effects, a suction pump is added over the shovel.
To better understand the make up and technical characteristics of the dredger which is the object of this invention, we will describe the images that form an integral part of this invention, without implying any obvious limitations or modifications that may arise, where:
In consideration of
The shovel as a whole (1) has a semi-cylindrical configuration with lateral walls (1a), which allows it to turn material and drag it in a circular motion while it advances, in the lower perimeter area of the shovel (1), it is equipped with a hard steel blade (9), with bolted replacement claws for possible hard material that the blade (9) cannot remove, so that it cuts and advances accumulating the material in the shovel (1).
The frame of the dredge where the shovel (1) is mounted is made up of a general rectangular configurated body, equipped with two lateral longitudinal beams (2), with an “I” shaped cross configuration, for the longitudinal area and three cross beams with an “H” shaped configuration (3), which are each positioned at each end and a third beam (5) located behind the shovel (1) where there are supports that can be regulated, which help to avoid the shovel (1) from becoming deformed, all of this is fixed with bolts. It has a top arch (5b) which serves to move the shovel (1) vertically. Right below this top arch (5b) there is a vertical grooved support (6) where a pivoting axle is inserted which allows to regulate the cutting height of the shovel (1), and once regulated, is fixed with dowels or bolts.
The skids (4), are four prism support structures, located inside the vertices where the end longitudinal beams (2) and cross beams (3) join, these skids (4) prevent the shovel (1) from sinking in the substrate to be cracked, since by being watertight and of a specific volume, they have the capacity to be flooded or filled with air, which allows to regulate the weight of the dredger machine. This is achieved by inserting compressed air through a valve (not illustrated), which extracts the water by air-pressure injection which comes out through a second valve (not illustrated), then these valves are closed once the cutting depth has been regulated.
At the coast of the country dredging is often used at the seabed to increase draught for larger ships. Existing machines dredging the surface leave an uneven bottom and there is no way to remove material and leave an even bottom at the same time. Leaving an even bottom would require a very high additional cost.
Excavators are also used over barges, but it is a risky operation due to the stability of the pontoon (ship) and the dimensions of the excavation.
With this new dredger of this invention, it is easier to remove material directly from land and immediately leave a flat surface at the seabed, which is possible because it i sable to closely regulate the cutting depth since the height of the shovel can be regulated and doing all of this is less time and Money, in addition to generating less environmental impact.
Filing Document | Filing Date | Country | Kind |
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PCT/CL2013/000073 | 10/9/2013 | WO | 00 |