JPH07268901A - Dredging device - Google Patents

Abstract

PURPOSE:To lift up mud with high concentration, and dispense with a swing wire by excavating and fluidizing a dirt bed on mud-earth layer by two pairs of drum cutters suspended from a raising-lowering frame body of a dredge, and taking it in by a vertical screw conveyor. CONSTITUTION:A pair of lower stage drum cutters 30 on both under sides of a vertical screw conveyor 40 suspended from a raising-lowering frame body 20A raised and lowered by a hoist and a pair of upper stage drum cutters 30 joined by links on the upper outsides of the lower stage drum cutters 30 so as to be freely tiltable, are respectively symmetrically arranged with each other. A tilting angle formed by the upper stage and lower stage drum cutters 30 is made large, and they are driven in rotation, and while excavating a dirt bed, they are settled and sunk in mud, and the tilting angle is made gradually small, and a dredging area is expanded. Fluidized mud is taken in from the lower end of the vertical screw conveyor 40, and plug transport is performed up to its destination by a pressurizing pump 50 of the raising-lowering frame body 20A. Since excavation is performed the inversely rotating bilaterally symmetrical drum cutters 30, horizontal directional reactions are offset to each other, and a lateral movement is prevented, so that a swing wire, a stopper or the like become unnecessary.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is applicable, for example, to seabeds, lakes,
The present invention relates to a dredging device used when dredging sludge and other soft mud accumulated at the intakes of rivers, ports and power plants.

[0002]

2. Description of the Related Art As a conventional dredging device, there is a pump type. In this pump type dredging device, a large-capacity pump is installed on a barge or the like, and a hose is extended from the pump to the bottom of the water such as the seabed or the bottom of the lake to suck up the soft mud with water. Then, the soft mud dredged in this way is mainly transported to the landfill by a pipeline. At the landfill site, after the mud is settled, the residual water is treated with a coagulant and then discharged.

[0003]

However, in the above-mentioned conventional dredging apparatus, the amount of water sucked up simultaneously with the soft mud is too large and a large-capacity disposal site is required, and the spillage treatment requires a large amount of money. There was a drawback that it required. In addition, in the case of pump dredging, it is necessary to stretch at least two swing wires diagonally to the seabed from the dredger in order to keep the dredger at a fixed position in the ocean during dredging.Unlike wide ocean, dredging in rivers and dams is required. In some cases, the swing width could not be sufficiently secured, which hindered efficient dredging. In addition, in an area where ships frequently travel, such as in a harbor, there is a problem that the stretched swing wires hinder the navigation of other ships.

[0004]

In order to solve these problems, the dredging device of the present invention is a dredging device which is mounted on a dredging ship and which is suspended by an elevating frame which is vertically movable by a winch hoist. The dredging device includes a vertical screw conveyor, a pressure pump connected to a discharge port of the vertical screw conveyor, a discharge pipe including an air nozzle for injecting compressed air, and a fixed installation on the elevating frame body. And a pair of drum cutters fixed symmetrically on both sides of the lower end of the vertical screw conveyor, and at least a left and right unit that is link-joined with the drum cutter and is disposed outside the upper portion of the drum cutter and tiltable in a vertical plane. The drum cutter is formed of a pair of drum cutters, and each of the drum cutters has a plurality of plate-like or rod-like cutters protruding from the outer periphery of a drum which is driven to rotate about a horizontal axis at substantially equal intervals.

[0005]

In the dredging device of the present invention, the tilt angle formed by the upper drum cutter is increased with respect to the lower drum cutter so that the drum cutter is landed on the seabed, and the drum cutter is rotationally driven to separate the cutter from the mud. By gradually submerging the entire dredging device into the mud, the tilting angle is gradually reduced to expand the dredging area, and the excavated and fluidized mud is sequentially taken in from the intake at the bottom of the vertical screw conveyor and vertically transport. In this way, the mud discharged from the discharge port above the vertical screw conveyor is sent to the pressure pump and pressurized, and compressed air is injected into the discharge pipe to transport it to the destination remote from the dredger. To be done.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 7 relate to an embodiment of the present invention, FIG. 1 is an overall schematic side view of a dredging device, FIG. 2 is a side view of a main part of the dredging device, and FIG. 3 is a sectional plan view taken along line AA of FIG. FIG. 4 is a sectional plan view of a drum cutter according to another embodiment, and FIG.
6 is a side view of the dredging device at the time of submarine subsidence, FIG. 6 is a side view of the dredging device at the time of dredging, and FIG. 7 is an overall vertical cross-sectional view of the vertical screw conveyor. As shown in FIG. 2, the dredging device 100 includes a vertical screw conveyor 40 vertically suspended in the center of a horizontal elevating frame body 20A made of shaped steel having pulleys 20b attached to the upper surfaces of both ends, and its auxiliary equipment. It is composed of a certain pressurizing pump 50, a discharge pipe 70, an air nozzle 60 for injecting compressed air provided in the middle of the discharge pipe 70, and a plurality of left and right symmetrical drum cutters 30 supported by the elevating frame 20A. The dredging device 100 configured as described above is suspended on the elevating frame body 20A and the pulleys 20b at both ends of the elevating frame body 20A.
The wire rope 20a wound around is moved up and down. That is, as shown in FIG. 1, the wire rope 20a goes through the winch hoist 2 while passing through the pulleys 10a, 10a installed on the top of the tower 10 standing upright on the deck of the dredger 90.
Moves back and forth through 0.

As shown in FIG. 7, the vertical screw conveyor 40 includes bearings 44, 4 in a vertical cylindrical casing 41.
A spiral screw 4 is attached to a rotary shaft 42 that is pivotally supported by
3, the screw 43 is rotationally driven together with the rotary shaft 42 by a hydraulic motor 46, and the soft mud and the like taken in from the lower end is discharged from an upper discharge port 47. As shown in FIG. 2, a discharge pipe 70 including a pressurizing pump 50 that is rotationally driven by a hydraulic motor and an air nozzle 60 that injects compressed air is connected downstream of the discharge port 47. It is composed of a flexible pipe and is connected from the dredger 90 to a remote destination. A plurality of pairs of left and right drum cutters 30, 30 and the like are symmetrically arranged on both sides of the lower end of the vertical screw conveyor 40, and fixed by supports 22 protruding from the elevating frame body 20A. That is, the lower drum cutters 30A, 30A are the two supports 22, 22 suspended from the elevating frame body 20A.
Bearing 3 at both ends of horizontal support 24 supported at both ends by
A rotary shaft 31 is pivotally supported via 1a. On the contrary,
The upper-stage drum cutters 30B and 30B are symmetrically linked to the lower-stage drum cutters 30A and 30A via the link 26, and are also pin-joined to the tip end of the piston rod 34a of the hydraulic cylinder 34 which is pin-joined to the elevating frame 20A. As the piston rod 34a moves back and forth, the tilt angle of the link 26 changes and its position changes.

The drum cutter 30, as shown in FIG.
All four are equipped with plate-shaped cutters 33 having sharp tips at substantially equal intervals on the outer periphery of a drum 32 that rotates around a horizontal rotation shaft 31 in parallel with the rotation shaft 31 in a removable manner. Bearings 31a that support both ends of the rotary shaft 31 of the lower drum cutter 30A are fixed to the support 24 described above. On the other hand, the rotary shaft 31 of the upper drum cutter 30B has the link 2
6 is supported by a bearing 31a. In the rotation direction of the drum 32, the lower right one in FIG. 2 is clockwise, the upper right one is counterclockwise, and the left half is in the opposite direction. Therefore, the mud excavated by the cutter 33 of the lower drum 32 is lifted up as it is and taken in as it is from the intake port at the lower end of the vertical screw conveyor 40. Also,
In the upper drum 32, the outer mud is excavated, inverted and sent obliquely downward, reaches the lowermost drum 32, and is taken into the vertical screw conveyor 40 by the procedure described above. The drums 32 are rotationally driven by hydraulic motors (not shown) provided independently of each other. The rotation speed of the drum 32 is set to about 10 to 20 rpm, and is adjusted by the hardness of the mud (generally lower in hard mud).

On the other hand, what is shown in FIG. 4 is a drum cutter 30 showing another embodiment of the present invention, and the difference from the embodiment of FIGS. 2 to 3 will be described. Body drum 32a sandwiched between links and links 26
In addition to the above, a cutter provided with an overhanging drum 32b attached to a rotary shaft 31 protruding through the support 24 or the link 26 and a bar-shaped protrusion having a sharp tip instead of a plate-shaped cutter 33 33.
With such a configuration, not only can mud be excavated in a wider range than those shown in FIGS. 2 and 3, but also
There is an advantage that the excavation effect is also given to the side surface of the drum 32.

The operation of the dredging device 100 of the present invention constructed as above will be described. Dredge device 10 of the present invention
After circling the dredger 90 equipped with 0 to the dredging site and stopping the ship, as shown in FIG. 5, the tilting surface of the upper drum cutter 30B is increased and the winch hoisting machine 20 is operated to lift the lifting frame 20A. Hold horizontally and gently drop into the sea. After the drum cutter 30 on the lower end side has landed on the seabed, the drum 32 is rotationally driven. The mud on the seabed is excavated by the rotational drive of the drum 32, and the drum cutter 30 gradually sinks into the mud layer, and eventually all the drum cutters 30 are buried in the mud layer, and the upper layer drum cutter 30B excavates and flows. The converted mud moves downward and is further moved to the vertical screw conveyor 40 by the lower drum cutter 30A.
Of the vertical screw conveyor 40 and is sucked into the vertical screw conveyor 40. As the drum cutter 30 sinks into the mud layer, as shown in FIG. 6, the tilt angle is reduced and the upper drum cutter 30B is moved outward to enlarge the dredging area. In this way, the mud that has entered the vertical screw conveyor 40 rises due to the rotation of the screw 43, is discharged from the discharge port 47, enters the pressurizing pump 50, is pressurized, and is discharged via a check valve (not shown). The compressed air that is pressure-fed to the feed pipe 70 and that is injected from the air nozzle (ejector) 60 provided at the inlet of the discharge pipe 70 is plug-transported (plugged) and transported over a long distance.

Since the dredging device 100 of the present invention excavates the mud layer on the seabed with the drum cutters 30 arranged symmetrically, the horizontal reaction force of the reaction force during excavation is offset and the vertical reaction force is offset. Since the dredging device 100 only receives the reaction force, the dredger 90 equipped with the dredging device 100 is prevented from moving laterally, and swing wires, such as a pump dredger,
No need for spuds. In addition, when the soil is submerged or buried in the mud layer at the beginning of the dredging work, the drum cutter in the upper stage can be moved inward, so that it is tapered as a whole and can be easily buried in the mud layer, resulting in high dredging efficiency.

[0012]

As described above, in the dredging device of the present invention, since the dredging range is expanded after the intake port is easily submerged in the mud layer on the seabed, the mud with a small amount of residual water can be continuously supplied at a high concentration. In addition to being highly efficient, it can be operated efficiently without obstructing the navigation of other vessels because it can omit swing wires and the like.

[Brief description of drawings]

FIG. 1 is an overall schematic side view of a dredging device according to an embodiment of the present invention.

FIG. 2 is a side view of a main part of the dredging device according to the embodiment of the present invention.

3 is a cross-sectional plan view taken along the line AA of FIG.

FIG. 4 is a cross-sectional plan view of a drum cutter according to an embodiment of the present invention.

FIG. 5 is a side view of the dredging device of the present invention during subsidence.

FIG. 6 is a side view of the dredging device of the present invention during dredging.

FIG. 7 is an overall vertical sectional view of a vertical screw conveyor according to an embodiment of the present invention.

[Explanation of symbols]

 10 Turret 10a Pulley 20 Winch Hoisting Machine 20A Elevating Frame Body 20a Wire Rope 20b Pulley 22 Support 24 Support 26 Link 30 Drum Cutter 30A Drum Cutter (Lower Stage) 30B Drum Cutter (Upper Stage) 31 Rotating Shaft 31a Bearing 32 Drum 32a Main Drum 32 Overhanging drum 33 Cutter 34 Hydraulic cylinder 34a Piston rod 40 Vertical screw conveyor 41 Casing 42 Rotating shaft 43 Screw 44 Bearing 45 Bearing 46 Hydraulic motor 47 Discharge port 48 Guide groove 49 Support plate 50 Pressurizing pump 60 Air nozzle 70 Discharge pipe 90 Dredger 100 dredging equipment

Claims (1)

[Claims] 1. A dredging device mounted on a dredger and suspended on an elevating frame which can be vertically moved up and down by a winch hoist, the dredging device being a vertical screw conveyor and a discharge port of the vertical screw conveyor. And a discharge pipe having an air nozzle for injecting compressed air, and a pair of drums that are fixed to the elevating frame and are fixed symmetrically on both sides of the lower end of the vertical screw conveyor. It is formed by a cutter and at least a pair of left and right drum cutters which are linked to the drum cutter and arranged outside the upper portion of the drum cutter and tiltable in a vertical plane. Each of the drum cutters is driven to rotate about a horizontal axis. Dredging device having a plurality of plate-shaped or rod-shaped cutters projecting at substantially equal intervals on the outer circumference of a drum to be formed.