JPH0665945A - Dredging equipment - Google Patents

Abstract

PURPOSE:To prevent sludge from sticking to the surface and the undersurface of inlet cutters by a method wherein the surface and the undersurface of the inlet cutters are scraped when the sludge is stuck thereto by auxiliary cutters in parallelogrammic section that are interposed between each of the upper and the lower inlet cutters. CONSTITUTION:Auxiliary cutters 110 are attached to a mudgathering plate 11 of an inlet device 5, and each of the auxiliary cutters is interposed between each of a plurality of inlet cutters 5b that are provided in tiers. Each of the auxiliary cutters 110 is formed in a link shape in parallelogrammic section, and helical compression springs are provided between each of upper and lower fulcrums and are made expandable and contractile in the vertical direction. The overall height of the helical compression spring is made the same as, or higher than a gap between each of the inlet cutters 5b. In the case where highly viscous sludge is stuck to the surface and the undersurface of the inlet cutters 5b, both the surface and the undersurface are scraped with the auxiliary cutters 110 and the sludge is removed. Thereby, excavation and agitation functions can be prevented from deteriorating, resulting in improvement of maintainability and dredging efficiency in protracted continuous operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dredging device used for dredging soft mud such as sludge accumulated in a water intake, a seabed, a lake, a river, a port, etc. of a power plant.

[0002]

2. Description of the Related Art Dredging of sludge such as sludge deposited on the seabed may cause a submersible pump to plunge into the sludge layer and suck it up.
Alternatively, it was done by scooping up the soft mud from the seabed with a grab bucket. However, this method cannot dredge a high-concentration soft mud, and because it sucks a large amount of seawater together with the soft mud, it has a poor pumping efficiency. In addition, the grab bucket method causes turbidity in seawater, There was a problem of causing secondary pollution.
Therefore, in order to solve these problems, a dredging device consisting of a vertical screw conveyor and an inlet device rotatably arranged at the lower end of this vertical screw conveyor was put into practical use, and it was placed near the upper end of the vertical screw conveyor. The soft mud discharged from the discharge port is pressurized by a pressure pump and pressure-fed to the discharge pipe via the check valve. Further, compressed air is pressure-injected from an air nozzle (ejector) provided in the middle of the discharge pipe for a long distance. A method of transportation has been proposed by the applicant.

FIG. 7 shows a conventional dredging device of this type, which is a dredging device 1 provided with a rotatable semi-circular mud collecting plate 11 on the outer periphery of an inlet device 5, in which the mud collecting plate 11 is dredged. After being rotated and opposed to the rear side in the direction, the inlet cutter 5 is slowly moved forward while the inlet cutter 5b is used to horizontally shear, stir, and fluidize the solidified mud layer at the dredging point to vertically move it. It is guided to the inside by the suction force due to the rotation of the screw blades 3 of the mold screw conveyor 2, and is moved up by the screw blades 3. At this time, the solidified soft mud is cut into slices by the inlet / cutter 5b and becomes soft and fluidized, but the foreign matter present in the soft mud cannot pass between the inlet / cutter 5b and is eliminated. To be done. The soft mud that has been lifted and transferred by the vertical screw conveyor 2 in this way is discharged from the discharge port 2a at the upper end and is conveyed to the next step.

When the soft mud is hard or has a strong adhesiveness, the soft mud adheres to the inlet cutter 5b itself as the operation continues, and this develops to clog the space between the inlet cutter 5b. The passage of the soft mud deteriorates,
Dredging and transportation capacity will be reduced. As a countermeasure in such a case, the inner surface of the mud collector 11 is projected horizontally and the inlet
The auxiliary cutter 11a, which is present between the cutters 5b, destroys and removes these clogged solid matters.

[0005]

However, in the case of treating clayey mud or soft mud, which is particularly sticky and highly viscous, these adhere and develop between the inlets and cutters and are conventionally used. In the horizontal flat plate-shaped complementary rib cutter, for example, as shown in FIG. 8, although a void is formed only in the sweep area of the auxiliary cutter, the high-viscosity mud still remains around the inlet cutter.
Therefore, not only the original excavation function and stirring function of the inlet / cutter are deteriorated, but also the driving power cost of the inlet device is increased, resulting in a decrease in dredging efficiency. Also,
Operation was often interrupted to remove the adhering mud, and cleaning was carried out by pulling it out of the sea, which was a maintenance disadvantage.

[0006]

In order to solve the above-mentioned problems, in the dredging device of the present invention, a vertical screw conveyor and an outer peripheral surface rotatably provided at the lower part of the vertical screw conveyor are provided. And an inlet device in which a plurality of stages of inlet cutters are vertically spaced from each other,
Dredging provided with a mud collecting plate having a substantially semicircular shape rotatably arranged on the outer circumference of the inlet device and having an auxiliary cutter provided on the inner peripheral surface so as to be sandwiched between the inlet and the cutter and protrude. In the device, the auxiliary cutter is formed by a parallelogrammatic link in cross section, and a compression coil spring is interposed between upper and lower fulcrums so that the auxiliary cutter is expandable and contractible in the vertical direction, and the total height of the parallelogrammic link. Was formed to be equal to or larger than the gap between the inlet and the cutter.

[0007]

In the dredging device of the present invention, even if the dredging work is performed on the highly viscous soft mud and the highly viscous soft mud adheres to the upper and lower surfaces of the inlet cutter, the parallel movement is caused by the rotation of the inlet cutter. An auxiliary cutter with a quadrilateral cross section is inserted between the upper and lower inlets and cutters,
Since the lower and upper surfaces of the cutter are rubbed against each other, viscous soft mud does not adhere and develop.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 to 6 relate to an embodiment of the present invention,
1 is an overall longitudinal sectional view of the dredging device, FIG. 2 is a bottom plan sectional view of the dredging device, FIG. 3 is a lower side view of the dredging device, and FIG. 4 is FIG.
IV-IV side view of FIG. 5, FIG. 5 is a front view of VV view of FIG. 4, and FIG. 6 is a vertical cross-sectional view of VI-VI view of FIG.

In the figure, 1 is a dredging device, 2 is a vertical screw conveyor, 2A is a casing, 3 is a screw (blade), 3a is a rotating shaft, 3b is an electric motor for driving the screw,
4 is a casing of the inlet device, 5 is an inlet device, 5a is an inlet cylinder, 5b is an inlet cutter,
6 is a bearing, 7 is a girth gear, 8 is a pinion gear, 9 is an electric motor, 10 is a protective cover, 11 is a mud collecting plate, 12 is a bearing,
13 and 14 are chain wheels, 15 is an electric motor, 16
Is a protective cover, and 110 is an auxiliary cutter.

As shown in the figure, the vertical screw conveyor 2
Has a cylindrical casing 2A, a screw rotating shaft 3a housed in the casing 2A and driven to rotate by a top electric motor 3b, and a screw blade 3, and the screw blade 3 causes sludge and the like. The soft mud is lifted and discharged from the upper discharge port 2a.

On the other hand, below the casing 2A of the vertical screw conveyor 2, a casing 4 of an inlet device 5 which rotates concentrically and with the same diameter as the casing 2A is suspended via a bearing 6, and an electric motor 9 and a pinion are provided. It can be rotationally driven via the gear 8 and the girth gear 7. At the lower end of the casing 4, inlet-cutters 5b having a toe-shaped plan view as shown in FIG. 2 are mounted in a plurality of stages on an inlet cylinder 5a having a large side opening. As shown in FIG. 2, the inlet cutter 5b is formed in a circular saw shape so as to shear the soft mud layer located on the outer circumference by rotation.

Further, a substantially semicircular mud collecting plate 11 is arranged on the outer circumference of the casing 4 so as to be supported by bearings 12 so as to cover the outer circumference of the inlet cutter 5b, and a motor 15 is provided via chain wheels 13 and 14. It is driven to rotate by. Reference numeral 16 is a protective cover for the chain wheel. An auxiliary cutter 110, which expands and contracts via a compression coil spring, is provided on the inner peripheral surface of the mud collecting plate 11 so as to be inserted into the gap between the inlet cutters 5b. Reference numeral 11b is a through hole for passing water.

As shown in FIG. 6, the auxiliary cutter 110 according to the present invention is composed of four blades 115, 116, 117 and 118, each of which has a parallelogram shape. Quadrilateral link 111,112,11
3, 114, the upper and lower parts are pivotally supported by through bolts 122, and the left and right pins are pivotally supported by through bolts 120.
Is fastened to the mud collecting plate 11 with a nut 130 through a through hole. The blade 115 and the blade 117 are pin-jointed with a hinge via a through bolt 122. Similarly, the blade 116 and the blade 118 have through bolts 122.
Is stopped by the hinge. Blade 117 and blade 1
A compression coil spring 140 is elastically mounted between 18 and the upper and lower pin fulcrums can be expanded and contracted. Then, as shown in FIG. 4, the total height H1 of the auxiliary cutter 110 is formed to be equal to or slightly larger than the inner dimension between the inlet cutters 5b, 5b.

The operation of the dredging device 1 of the present invention constructed as above will be described. The dredger equipped with the dredging device 1 of the present invention is transported to the dredging site, stopped, and then the electric motor 15 is driven and adjusted so that the mud collecting plate 11 comes to the back side in the dredging direction. After that, the vertical screw conveyor 2 is gently lowered until it reaches the bottom of the sea. After the inlet device 5 (specifically, the inlet cutter 5b) and the mud collecting plate 11 are landed and buried in the seabed soft mud layer, the electric motor 3b is driven to rotate the screw blades 3 and simultaneously the electric motor 9 is driven. When the inlet cutter 5b is rotated, the seabed soft mud layer is sheared, agitated, and fluidized, and the suction force generated by the rotation of the screw blades 3 successively passes through the opening of the inlet cylinder 5a and enters the apparatus, whereupon it rises. It is transported, reaches the upper part of the vertical screw conveyor 2, is discharged from the discharge port 2a, and is transported to the final place via the electromagnetic flow meter, the check valve, the pressure pump, and the discharge pipe provided in the next process.

Unlike the submersible pump, the transportation by the screw blades 3 of the vertical screw conveyor 2 mainly carries out the vertical transportation of the solid soft mud without much liquid. During this time, foreign matter mixed in the soft mud layer is blocked by the inlet cutter 5b and prevented from entering the inside.

However, even if there is no foreign matter, the hardened mud, the originally hard mud, or the strongly softened mud gradually adheres to and develops on the outer periphery of the inlet cutter 5b as the operation continues, and finally, Is the upper and lower inlet cutters 5b
It may be clogged due to close contact with each other across the space, and if this state covers the entire surface of the inlet / cutter 5b, it will be difficult for the soft mud to pass, and the amount of passage will be extremely reduced, drastically reducing the dredging capacity. To do. In order to avoid this state, the auxiliary cutter 110 that constantly expands and contracts via the compression coil spring is inserted into the gap between the inlets and cutters 5b to prevent the formation of clogging.

As described above, according to the present invention, in normal operation, only the soft mud excluding foreign matter can be transported at a high concentration and with little excess water, and the inlet cutter 5b can be clogged. Since the auxiliary cutter 110 is provided so as to prevent the occurrence of the above, continuous stable operation can be continued even with highly viscous soft mud. When the parallelogram link is used as in the present embodiment, the inlet cutter 5b can be rotated in the opposite direction without any problem, but the triangular link in the left half of FIG. 4 can be used. In this case, the inlet cutter 5b must be used while moving from the left side to the right side in FIG.

[0018]

As described above, in the dredging device of the present invention, since the auxiliary cutter provided on the mud collecting plate is swung up and down depending on the gap between the inlet and the cutter, Even if the highly viscous soft mud is dredged, it is prevented from adhering and developing on the upper and lower surfaces of the inlet cutter. Therefore, the inlet cutter is always stable with no deterioration in excavation action and stirring function, improving the maintainability and enabling long-term continuous operation, resulting in an improvement in dredging efficiency.

[Brief description of drawings]

FIG. 1 is an overall vertical cross-sectional view of a dredging device showing an embodiment of the present invention.

FIG. 2 is a bottom plan cross-sectional view of the dredging device showing the embodiment of the present invention.

FIG. 3 is a bottom side view of the dredging device showing the embodiment of the present invention.

FIG. 4 is a side view taken along line IV-IV of FIG.

5 is a front view taken along line VV of FIG. 4. FIG.

6 is a vertical sectional view taken along line VI-VI of FIG.

FIG. 7 is an overall vertical sectional view of a conventional dredging device.

FIG. 8 is a partial vertical sectional view for explaining a sweeping state by a conventional auxiliary cutter.

[Explanation of symbols]

 1 Dredging Device 2 Vertical Screw Conveyor 2A Casing 2a Discharge Port 3 Screw Blade 3a Rotating Shaft 3b Electric Motor 4 Casing 5 Inlet Device 5a Inlet Tube 5b Inlet Cutter 6 Bearing 7 Garth Gear 8 Pinion Gear 9 Electric Motor 10 Mud Cover 11 Auxiliary cutter 12 Bearing 13 Chain wheel 14 Chain wheel 15 Electric motor 110 Auxiliary cutter 111, 112, 113, 114 Link 115, 116, 117, 118 Blade 120 Through bolt 122 Through bolt 130 Nut 140 Compressed coil spring H Gap between inlets H1 auxiliary Total height of cutter

Claims (1)

[Claims] 1. A vertical screw conveyor, an inlet device provided rotatably at a lower portion of the vertical screw conveyor and provided with a plurality of stages of inlet cutters on an outer peripheral surface thereof and vertically spaced apart at appropriate intervals, and the inlet. A dredging device provided with a mud collecting plate having a substantially semicircular shape rotatably arranged on the outer periphery of the device and having an auxiliary cutter provided on the inner peripheral surface so as to project in the gap between the inlet and the cutter. The auxiliary cutter is formed by a parallelogrammatic link in cross section, and a compression coil spring is interposed between the upper and lower fulcrums so that the auxiliary cutter can be expanded and contracted in the vertical direction. A dredging device with a clearance equal to or greater than the gap between the inlet and cutter.