JP6828226B2 - Backfill prevention device for pump dredger - Google Patents

Description

The present invention relates to a backfill prevention device for a pump dredger that dredges underwater sediment in a harbor or the like.

Conventionally, as a device for dredging the bottom sediment of a harbor or the like, a device using a pump dredger is known (see, for example, Patent Document 1).

As shown in FIGS. 4 and 5, the pump dredger 1 includes a ladder 3 inserted into the water from the dredger main body 2 toward the bottom A, a turning means 4 for turning the rudder 3 together with the dredger main body 2, and a tip of the rudder 3. A cutter head 5 arranged in a portion, a sediment transfer pipeline 6 having a suction port 6a opened at the tip of a ladder 3, a suction pump 7 connected to the sediment transfer pipeline 6, and a spat 8 driven into the water bottom A. And an elevating means 9 for moving the ladder 3 up and down.

Then, in the dredging work by the pump dredger 1, the spat 8 is driven into the water bottom A, the rudder 3 is swiveled together with the dredger main body 2 by the swivel means 4 around the spat 8, and the earth and sand of the water bottom A is removed by the cutter head 5 at the tip of the rudder. The excavated earth and sand are sucked up by the suction pump 7 through the earth and sand transfer pipeline 6 together with the surrounding seawater, and directly transferred to the earth dump by pumping.

In the figure, reference numeral 4a is an operation wire constituting the turning means 4, and reference numeral 4b is an anchor. The operation wires 4a and 4a are unwound and wound by a winch installed on the ship to perform a dredging vessel. The rudder 3 rotates together with the main body 2.

This series of dredging work is repeated every time the pump dredging vessel advances, and the front of the already dredged water bottom surface (hereinafter referred to as the already dredged surface) is sequentially dredged.

Japanese Unexamined Patent Publication No. 51-39937

However, in the conventional technique as described above, as shown in FIG. 6, when excavating the earth and sand on the bottom A, the earth and sand B is scraped up to the already dredged surface C side by the rotation of the cutter head 5, and the earth and sand transfer pipeline 6 There was a problem that it was not sucked through and was backfilled to the already dredged surface C side.

Therefore, conventionally, in consideration of this backfilled earth and sand, it is necessary to secure the planned dredging depth by excavating the earth and sand deeper than the planned dredging ground height L (so-called extra digging). There was a problem of poor work efficiency.

Therefore, in view of such a conventional problem, the present invention has been made for the purpose of providing a backfill prevention device for a pump dredger capable of preventing backfilling at the time of dredging and efficiently performing dredging work. ..

The feature of the invention according to claim 1 for solving the conventional problem as described above includes a ladder inserted into the water toward the bottom of the water and a cutter head arranged at the tip of the ladder. a backfill prevention device of the pump dredger sediment excavated is to be sucked up through the sand transfer line by the cutter head is supported from the cutter head of the ladder tip backwards, central damming disposed centrally A backfill prevention body including a portion and a lateral damming portion extending diagonally forward from both sides of the central damming portion toward the cutter head side is provided.
The backfill prevention body is in a backfill prevention device for a pump dredger that has landed at the time of excavation and is configured to separate the cutter head side and the rear side of the rudder tip portion.

The feature of the invention according to claim 2 is that, in addition to the configuration of claim 1 , the backfill prevention body is reinforced with a backfill prevention body main body made of an elastic material and a rigid body supporting the backfill prevention body main body. It has a frame.

As described above, the backfill prevention device for the pump dredger according to the present invention includes a rudder inserted into the water toward the bottom of the water and a cutter head arranged at the tip of the rudder, and is excavated by the cutter head. A backfill prevention device for a pump dredger that allows the collected earth and sand to be sucked up through a sediment transfer pipeline, and is provided with a backfill prevention body supported behind the cutter head at the tip of the rudder. Is settled at the time of excavation and is separated from the cutter head side of the rudder tip and the rear side thereof, thereby preventing backfilling of earth and sand at the time of excavation to the already dredged surface side. Dredging work can be performed efficiently without the need for extra digging.

Further, in the present invention, the backfilling prevention body is formed with a side damming portion extending toward the cutter head side, so that it is possible to suitably prevent the backtracking of excavated earth and sand and to fill it. It is possible to increase the rigidity of the return prevention body and suppress deformation due to water flow or the like.

Further, in the present invention, the backfill prevention body includes a backfill prevention body main body made of an elastic material and a reinforcing frame made of a rigid body supporting the backfill prevention body main body, whereby the backfill prevention body is provided. The main body can be maintained in a desired shape, and since the backfill prevention body main body is made of an elastic material, it is not easily damaged and can be easily replaced even when worn.

A partially enlarged side view showing a backfill prevention device for a pump dredger according to the present invention, (b) is a bottom view, and (c) is a front view. (a) is a partially enlarged end view showing the attached state of the bent portion of the backfill prevention body main body in FIG. 1, and (b) is a cross-sectional view showing the attached state of the central damming portion. (a) is a partially fractured side view showing the state of the tip of the ladder at the time of excavation, and (b) is the same plan view. It is a side view which shows an example of a pump dredger. It is a plan view of the same as above. It is a side view which shows the state of the rudder tip part at the time of excavation by a conventional pump dredger.

Next, an embodiment of the backfill prevention device for the pump dredger according to the present invention will be described based on the examples shown in FIGS. 1 to 5. The same configuration as the above-mentioned conventional example will be described with the same reference numerals, and reference numeral 1 in the drawing is a pump dredger.

Similar to the conventional examples shown in FIGS. 4 and 5, the pump dredger 1 includes a rudder 3 inserted into the water from the dredger main body 2 toward the water bottom A, a turning means 4 for turning the rudder 3 together with the dredger main body 2, and a turning means 4. It includes a cutter head 5 arranged at the tip of the rudder 3, a sediment transfer pipeline 6 having a suction port 6a opened at the tip of the ladder 3, and a suction pump 7 connected to the sediment transfer pipeline 6. ..

In the dredging work by the pump dredger 1, the spat 8 is driven into the water bottom A, the rudder 3 is swiveled together with the dredger main body 2 by the swivel means 4 around the spat 8, and the earth and sand of the water bottom A is removed by the cutter head 5 at the tip of the rudder 3. The excavated earth and sand B is sucked up by the suction pump 7 through the earth and sand transfer pipeline 6 together with the surrounding seawater, and is directly transferred to the earth dump by pumping.

This series of dredging operations is repeated every time the pump dredging vessel 1 advances, and the front of the already dredged water bottom surface (hereinafter referred to as the dredged surface C) is sequentially dredged.

Further, the pump dredger 1 is provided with a backfill prevention device so that the excavated earth and sand B can be prevented from being backfilled to the already dredged surface C side.

As shown in FIG. 1, the backfill prevention device includes a backfill prevention body 10 supported behind the cutter head 5 at the tip of the ladder 3, and the backfill prevention body 10 has its lower edge attached during excavation. It is bottomed so as to separate the cutter head 5 side of the tip of the ladder 3 from the rear side (existing dredged surface C side).

The backfill prevention body 10 includes a backfill prevention body main body 11 made of an elastic material and a reinforcing frame 12 for supporting the backfill prevention body main body 11, and laterally extending toward the cutter head 5 side on both sides. The dams 13 and 13 are formed.

The reinforcing frame 12 is formed of a rigid body such as a steel material, and has frame members 12a and 12a for bending portions whose base ends are fixed to the side surfaces of the tip end portion of the ladder 3, and under the ladder 3 along both side surfaces and the lower surface of the ladder 3. It is provided with a frame material 12b for a notch portion arranged at a side edge portion.

The bent portion frame material 12a is made of H-steel or the like, the base end is fixed to the side surface of the rudder 3 by welding, bolts, or the like, and the tip end side extends diagonally toward the tip end side of the rudder 3. Further, the frame member 12a for the bent portion is supported by the ladder 3 at a desired position in the longitudinal direction via the reinforcing support member 12c.

On the other hand, the cutout frame material 12b is formed in a U shape by an L-shaped angle material or the like, is fixed to the lower edge of the ladder 3 by welding or the like, and projects from the outer surface of the ladder 3.

Then, as shown in FIG. 2, the reinforcing frame 12 is detachably fixed to the frame material 12a for the bent portion and the frame material 12b for the notch portion by bolting or the like at the upper edge portion of the backfill prevention body main body 11. The upper edge of the backfill prevention body 10 is formed.

The backfill prevention body 11 is made of a flexible plate material such as a rubber plate or a synthetic resin plate, and is directed diagonally forward from both sides of the central blocking portion 11a arranged in the center and the central blocking portion 11a. It is provided with a bent portion 11b that has been bent.

In the backfill prevention body main body 11, the upper edge portion of the central damming portion 11a is fixed along the cutout portion frame material 12b of the reinforcing frame 12, and the upper edge portion of the bent portion 11b is the bent portion frame material 12a. It is fixed along.

The bent portion frame 12a and the bent portion 11b form a side damming portion 13 that extends obliquely toward the cutter head 5 side in the backfill prevention body 10.

Further, in the backfill prevention body main body 11, a notch portion 11c for fitting is formed in the central portion of the central dam portion 11a, and the notch portion 11c is fitted with the lower edge of the ladder 3 and the edge portion thereof. Is fixed to the notch frame material 12b.

Since the side damming portion 13 is formed in the backfill prevention body 10, the backfill prevention body body is made of a flexible plate material such as a rubber material while preventing the earth and sand from escaping due to turning. The rigidity of 11 is increased, and deformation due to the influence of water flow or the like is suppressed.

Further, since the backfill prevention body main body 11 is a flexible plate material such as a rubber material, it is not easily damaged even when pressed against the water bottom A, and it can be attached to and detached from the reinforcing frame 12, so that it is easy to wear when worn. It can be exchanged for.

Next, the dredging operation using the pump dredging vessel 1 according to the present invention will be described. The same reference numerals are given to the same configurations as those in the above-described embodiment, and the description thereof will be omitted.

First, the work boat 2 is moved to the dredging target area, the spat 8 is driven into the water bottom A at that position, the elevating means 9 is operated to lower the tip side of the ladder 3, and the cutter head 5 and the backfill at the tip of the ladder 3 are backfilled. The preventive body 10 is landed on the bottom.

Then, the cutter head 5 and the suction pump 7 are operated, the turning operation of the work boat 2 is started, the rudder 3 is swiveled together with the dredger main body 2, and the earth and sand on the bottom A is excavated by the cutter head 5 at the tip of the rudder 3. The excavated earth and sand are sucked up by the suction pump 7 through the earth and sand transfer pipeline 6 together with the surrounding seawater, and directly transferred to the earth dump by pump pumping.

Then, this series of dredging operations is repeated for each movement of the pump dredging vessel 1, and the front of the existing dredging surface C is sequentially dredged.

In each dredging operation, as shown in FIG. 3, the earth and sand B scraped up by the cutter head 5 when the bottom A is excavated is blocked by the backfill prevention body 10.

Further, the earth and sand B blocked by the backfill prevention body 10 is sucked from the suction port 6a together with the surrounding seawater together with the earth and sand being excavated through the earth and sand transfer pipeline 6, and is backfilled to the already dredged surface C side of the earth and sand B. Is prevented.

Therefore, in this pump dredging vessel 1, raising of the existing dredging surface C due to backfilling of earth and sand is suppressed, extra digging becomes unnecessary, and excavation may be performed substantially according to the planned dredging height.

The shape of the backfill prevention body 10 is not limited to the above-described embodiment, and may be, for example, a plate material curved in an arc shape.

A Water bottom 1 Pump dredger 2 Dredger body 3 Ladder 4 Swivel means 5 Cutter head 6 Sediment transfer pipeline 7 Suction pump 8 Spat 9 Lifting means 10 Backfill prevention body 11 Backfill prevention body body 12 Reinforcement frame 13 Side dam

Claims (2)

Filling a pump dredger equipped with a ladder inserted into the water toward the bottom of the water and a cutter head arranged at the tip of the ladder so that the earth and sand excavated by the cutter head can be sucked up through the earth and sand transfer pipeline. It is a return prevention device
A central dam that is supported behind the cutter head at the tip of the rudder and is located in the center, and a lateral dam that extends diagonally forward from both sides of the central dam toward the cutter head. Equipped with a backfill prevention body with a part
The backfill prevention body is a backfill prevention device for a pump dredger, which has landed at the time of excavation and separates the cutter head side and the rear side of the rudder tip portion. The backfill prevention device for a pump dredger according to claim 1 , wherein the backfill prevention body includes a backfill prevention body main body made of an elastic material and a reinforcing frame made of a rigid body that supports the backfill prevention body main body. ..

Images