JPS59161525A - Working ship - Google Patents

Abstract

PURPOSE:To increase the strength of the pivotal portion of a working ship by a method in which a vertically rocking main spud and a vertically movable auxiliary spud are attached to the back end of a dredger, and an addition weight, a bottom plate and a basal end are pivotally attached to the tip of the main spud in a slidably movable manner toward the longitudinal direction of the dredger. CONSTITUTION:A ladder 6 is pivotally supported on the front of a ship in a vertically rocking manner, and a main spud 8 is pivotally supported on the back end in a vertically rocking manner by a gantry B provided on the ship. Also, an auxiliary spud 15 is attached to the back end in a vertically movable manner. A part 8b to land the seabed is pivotally supported on the tip of the main spud 8 in a vertically rocking manner and an addition weight 8c is also attached to the tip of the main spud 8. The basal end of the main spud 8 is pivotally supported on the spud carriage 10 in a vertically rocking manner, and the spud carriage 10 is designed to slide in the longitudinal direction of the ship by means of an oil- pressure cylinder 12. The strength of the pivotal portion the main spud 8 and the ship 5 during the dredging operation can thus be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a work boat, such as a dredger, which is equipped with a working device at one end of the hull and a pivot shaft member of the hull at the other end.

Conventional pump dredgers are provided with a main spud 1 and an auxiliary spud 2 as shown in FIGS. 1 and 2, or a third spud.
The complete Christmas tree mooring device 3 and wires 4 shown in FIGS. As a result, dredging is performed while the hull 5 is turned left and right around the main spud 1 or the Christmas tree mooring device 3.

The disadvantage of the spant method is that there are many accidents where the horizontal movement of the hull 5 during waves causes a bending moment in the spant 1.2, causing it to break, and in the past, it has been found that "swells" with an average wave period of about 7 seconds or more occur. In sea areas where wave height is 0.4・～0
, 5 m is the limit of use. Under even more severe sea conditions, one-way Christmas tree mooring is used.

On the other hand, the Christmas tree method can withstand use under harsh sea conditions compared to the spud method;
It has the following main drawbacks.

(1) Compared to the spud method, the ability to maintain the position of the hull 5 is inferior, and this method cannot be removed unless the dredging is carried out with high precision.

(2) The Christmas tree wire 4 cannot be stretched to a sufficient length in narrow sea areas. If the length of the wire 4 is short, the wire 4 may break or the anchor may become insufficiently held.

(3) Since the pump dredger performs dredging while moving the hull 5 forward, it is necessary to replace the anchor for the Christmas tree wire 4, and compared to the spud method (J band work is increased).

Furthermore, one of the reasons why the dredging efficiency of conventional pump dredgers is reduced during waves and the operating limit is low is that the vertical and longitudinal movements of the canterhead at the tip of the lug 6 become large due to the shaking of the ship during waves. This results in a decrease in the amount of soil sucked in and damage to dredging equipment such as cutters and cutter shears (7).

The reason for the poor wave resistance of conventional pop dredgers is that, as mentioned above, the mooring device is weak and cannot withstand large waves, and the top and bottom of the cutter head. This is because FIj and back and forth movements become large.

One way to solve these problems is to climb onto a jack-up device and hold the hull above the water. This method has already been built, but it has the drawbacks of extremely high construction costs and operational limitations due to seabed conditions. be.

Therefore, an object of the present invention is to provide a work boat that has a simple structure that costs the same as a conventional pump dredger, has improved mooring performance and swaying performance, and has improved wave resistance. .

Therefore, the work boat of the present invention is provided with a working device at one end of the hull, and a pivot member suspended via a wire from a gantry provided on the hull at the other end, and the pivot shaft member is suspended from a gantry provided on the hull. is formed by a turning tip shaft whose tip penetrates into the seabed, and an arm shaft provided obliquely to this tip shaft, and the base end of this arm shaft rotates around the arm shaft. It is attached to the ship body via a horizontal shaft that movably supports it and a drive device that moves the ship body relative to the arm shaft, and the turning tip is attached to the tip of the turning shaft member. It is characterized in that an additional weight is provided that can increase the ground pressure of the shaft and the tension of the wire.

Hereinafter, embodiments of the present invention will be explained with reference to the drawings.
5 and 6 show a work boat as a first embodiment of the present invention, with FIG. 5 being a plan view thereof and FIG. 16 being a side view thereof.

The work boat of this embodiment is equipped with a dredging device A and a lug 6 as two working devices at one end of the boat 14.5, and dredging is carried out by swinging the hull 5 from side to side using a swing wire 7. At the other end of the hull 5,
A main spud 8 as a pivot shaft member of the hull 5 is connected to the spant carriage 1 () by a trunnion 9 as a horizontal shaft, and a roller or sliding surface (not shown) is provided between the spud carriage 10 and the hull 5. The spud carriage 10 is moved forward and backward by moving up to the hydraulic cylinder 12.

The spud carriage 10 and the hydraulic sill 12 constitute a drive device that moves the hull 5 relative to the main spud 8.

The main spud 8 has a T& shape with a turning tip shaft portion 8b whose tip is penetrated into the seabed, and an arm shaft 8a provided obliquely to the tip shaft portion 8b. The arm shaft 8a and its tip shaft portion 8 are arranged so that the conical tip of the arm shaft 8b penetrates the seabed and is almost perpendicular to the seabed surface.
b is pin-coupled to form a required angle.

And Lord Suba Ndo 8 is Suba Ndo Entry 13
It is suspended by a wire 14 and lifted up and down by a winch or the like (not shown).

On the other hand, an additional weight (15
An ingot of 0 to 200 tons is divided into 10 to 20 pieces and attached to the arm shaft 8a) 8c, and the tip shaft part 8b receives a reaction force from the seabed during dredging work by the dredging device A. The required tension is created in the wire 14.

A vertical auxiliary spud 15, which is used when replacing the main spud 8, is provided at the stern of the hull 5 via a spud keeper 16.

Since the work boat of the present invention is configured as described above, during dredging work, the turning tip shaft part '8b at the tip of the main spud 8 receives a reaction force R from the seabed due to the additional weight 8c, and the wire 14 Even if the required tension T is generated and an external force due to waves is applied to the hull 5 during waves, the hull 5 and the main spud 8 are in a range where the reaction force R and the tension T do not become zero.
The relative angle with respect to the arm axis 8a does not change.

Therefore, the main spud 8 is fixed to the hull 5 and rotates.

On the other hand, it is possible to advance the hull 5 by a predetermined distance by extending the hydraulic sill 12 while keeping the main spant 8 on the ground. After the hydraulic sill 12 has reached its full stroke, the auxiliary spant 15 is moved to the seabed. The main spud 8 is lifted by the wire 14 and the winch, and the turning end shaft portion 81 at the tip of the main spud 8 is pulled out from the seabed.

Then, the hydraulic cylinder 12 is retracted to move the bad carriage 10 forward (to the right in Fig. 6), and the main spant 8
After changing the stroke, the auxiliary spud 15 is pulled out and the hydraulic sill 12 is extended to move the hull 5 forward again.

Alternatively, by performing the operation opposite to the above and moving the spud carriage 10 in a direction that draws it relatively toward the hull 5 using the hydraulic sill 12 while keeping the main spud 8 on the ground, the hull 5 can be moved astern. I also take it.

In addition, in order to prevent the auxiliary spud 15 from breaking in waves, a shock absorber or the like is provided in the spud keeper 16 so that it can be used even in waves.

Next, the strength of the main spud 8 during waves will be explained. During waves, the main spud 8 receives a large horizontal force due to the horizontal movement of the hull 5.

In a dredger that uses a conventional vertical spud, as shown in Figures 7 and 8, when the hull 5 receives wave force from the side, the width of the hull 5 is small, so the hull 5 easily bends. Although the ship's hull 5 is tilted, the left-right sway (SAg) of the hull 5 becomes large, but the force acting on the main spud 1 in the left-right direction is relatively small.

When the Matoko hull 5 receives wave force from the longitudinal direction of 6, as shown in Figures 9-1 and 510, the hull is long, so the inclination of the hull is small, and the hull sways (surge).
) is relatively small, but a large longitudinal force acts on the main spud 1, and a large bending moment acts on the spunt cross section near the lower end τj of the spud keeper 17 that supports the main spud 1. Furthermore, due to the synchronization of the natural period of the ship's back and forth rocking with the wave period, an even more extraordinary bending moment may act.

In the work boat of the present invention, the hull 5 is supported diagonally by the arm shaft 8a and rigidly restrained in the longitudinal direction.
The force acting on the vertical spud 1 is very small compared to the vertical spud 1.

Further, the main spant 8 is connected to the hull 5 by the horizontal axis of the sub-end caliper sock 10 and the trunnion 9, and the tip shaft portion 8b is pin-coupled to the arm shaft 8a.
The bending moment generated on the shaft 8a of the ship body 5 is very small, and the force acting in the longitudinal direction of the hull 5 is mainly axial force, which allows the bridge to withstand extraordinary forces.

On the other hand, although a bending moment is generated at the conical tip of the pivoting tip shaft portion 8b, its value is small because the lever from the tip of the spud is small.

When a force acts in the left-right direction of the hull, a bending moment is generated as in the conventional spud, but unlike the conventional cylindrical cross-section, the spud of the present invention has a rectangular cross-section that is resistant to lateral bending. It is easy to reinforce.

Regarding pitching of the hull in waves, in the conventional vertical spud, there is a clearance between the spant and the spud keeper, so no restraining force is applied to the vertical movement of the hull. Therefore, the hull 5
In the waves, the vertical oscillation (Hea
vi 昭) and pitching (Pitching).

In comparison, when the spud structure of the present invention is adopted, the vertical movement of the hull 5 is restricted at the stern, so the
As shown in comparison with FIG. 1 (conventional example) and FIG. 12 (present invention), the pitching of the hull 5 is reduced to 115 to 1/10,
Accordingly, the up-and-down movement of the cutter head as the dredging device A is also significantly reduced.

In other words, most of the moment that causes the hull 5 to pitch is caused by fluctuations in the drawing force of the wire 14 suspending the main spant 8 given by the additional weight 8c and in the ground pressure of the turning end shaft 8b. absorbed by.

Regarding the forward and backward movement of the hull 5 during waves, with the conventional vertical spud, dredging operation is difficult due to clearance between the spud and the spant keeper, out of the area of the spud due to the longitudinal inclination (Trim) of the hull S, and deflection of the spud. At times, the hull moves in the fore-and-aft direction due to wave external forces acting on the hull 5 and fluctuations in the tension generated in the swing wire.

In comparison, when the spud of the present invention is adopted,
Since there is no clearance between the main spud 8 and the hull 5, and the amount of deformation of the main spud 8 is very small, the forward and backward movement of the hull 5 and the cutter head is small, allowing for highly accurate dredging work.

Comparing the oscillation performance in waves between the conventional vertical spud and the inclined spud of the present invention, Figures 13 to 15 show that the 6'0OOps type pump dredger has the tilted spud of the present invention. The graph shows the calculation results of the vertical and horizontal movements of the cutter head during diagonal waves when using a vertical spud and when using a conventional vertical spud. Indicate the case,
The dashed line graph shows the case of the present invention.

These calculations ignore the force/resistance force that the cutterhead receives from the seabed, but from this it is possible to estimate the magnitude of the impact force from the seafloor that is applied to the cutterhead during waves.

As is clear from Figures 13 to 15, it is extremely difficult for conventional pump dredgers to perform dredging work in sea areas where "swells" with a wave period of 7 to 10 seconds occur. By applying this method, it is expected that the working limit wave height will be approximately doubled or more.

It can also be seen that not only the up-and-down movement of the cutter head 9, but also the lateral movement and the fluctuation force generated in the swing wire 7 are also reduced due to the reduction in bow rocking (Yau+ing).

In this way, according to the work boat as the first embodiment of the present invention, the following effects can be obtained.

(1) The main spud 8 can be used as a pivot member of the hull 5 even under severe sea conditions.

Compared to the conventional method of reinforcing spuds (increasing the plate thickness and diameter), this method costs less and is superior in strength.

(2) Vertical, back-and-forth, and side-to-side movements of the canterhead to the working device in waves are reduced, improving dredging accuracy and work efficiency.

(3) The center of left and right turning of the hull 5 during dredging (grounding point of the tip shaft portion 8b of the spud) is further back than the tail end of the conventional method (111), and the dredging width is larger for the same swing angle. This improves efficiency.

Figures 16 and 17 show a work boat as an example of the vS2 of the present invention, with Figure 16 being a side view showing the main parts thereof, and Figure 17 being a plan view showing the main parts thereof. .

In this second embodiment, a dredger is shown in which a link mechanism is provided as a drive device for moving the hull 5 relative to the main spud 19 without using the spud carriage 10.

A bendable main spud 19 is attached to the stern of the hull 5 of the work boat.
The main spud 19 has a spud main body connecting arm 19a which is pivotally connected at its base end to the stern protruding support part 18 of the hull 5 by a trunnion 20 and can swing, and a trunnion 21 attached to this arm 19a. Mediator! ) and a main spud 19b which can extend obliquely to the seabed.

The spud body 19b is suspended by the entry 13 of the hull 5-1 via the wire 22, as in the first embodiment.

Also, as a drive mechanism for swinging the connecting arm 19a,
A hydraulic sill 23 is mounted between the hull 5 and the arm 19a.

The two-dot chain line in FIG. 16 indicates the relative position of the natural pad 19 with respect to the hull 5 when the hydraulic sill 23 is in the contracted state.

The operation and effect of this second embodiment are almost the same as those of the first embodiment described above, but in this second embodiment,
With the above configuration, the spud carriage 10 (fifth and sixth
(see figure) is not required, so the space for installing the spud carriage 10 in the hull 5- is saved.

In addition, during waves, the reaction force R from the seabed ground acting on the tip of the main spud 19 can be received by the hydraulic sill 23 and the support part 18 fixed to the hull 5. The spunt carry 71, which is necessary for the spunt carry 7 method, which moves back and forth.
There is also the advantage that no guide member and extensive reinforcement of the hull 5 are required.

As detailed above, according to the work [111] of the present invention,
A working device is provided at one end of the lid body, and a rotating shaft member is provided at the other end via a wire from a gantry provided on the hull, and the rotating shaft member is attached to the seabed. It is formed by a turning tip shaft that penetrates the tip, and an arm shaft provided obliquely to the tip shaft, and the base end of this arm shaft rotatably supports the arm shaft. It is attached to the hull through a horizontal shaft that moves the hull relative to the arm shaft, and the swinging tip shaft is grounded to the tip of the swinging shaft member. With a simple configuration in which a τ1 weight is provided that can increase the pressure and the tension of the wire, the pivoting shaft member with the ship body can maintain sufficient strength and reliability when the pivot shaft member is used. This makes it easier to insert and remove the turning tip shaft from the seabed, which has the effect of greatly improving work efficiency.

[Brief explanation of drawings]

Figures 1 and 2 show an example of a conventional work boat. Figures 1 and 1 are its side views, Figure 2 is its top view, and
The figures show another example of a conventional work boat, with Fig. 3 being a side view thereof, Fig. 4 being a plan view thereof, and Figs. 5 and 6 showing a working port as a first embodiment of the present invention. 1), and the fifth
The figure is a plan view thereof, FIG. 6 is a side view thereof, FIGS. 7 and 8 are explanatory diagrams when a conventional working IJF' is subjected to wave force in the left and right directions, and FIGS. 9 and 10 are The figure is an explanatory diagram when a conventional work boat is subjected to wave force in the longitudinal direction, and Fig. 11 and Fig. This is an explanatory diagram of the second downward movement of the cutter head and the
3 to 15 are graphs that compare and show the characteristics of a conventional work boat and a work boat of the present invention, and FIGS. 16 and 17 show a work boat as a ptS2 embodiment of the present invention.
FIG. 1G is a side view showing the main part, and FIG. 17 is a plan view showing the main part. 1. Vertical spud, 5. Hull, 6. Rudder, 7
・・Swing wire, 8・・Main spant as a turning shaft member, 8a・・Arm axis, 81″・Pa・Swivel tip shaft part, 8c・・i;j Load amount, 9・・Trunion with horizontal axis ,]0...Spud carriage, 12...Hydraulic cylinder, 13...Gantry, 14...Wire, 15...Auxiliary spud, 16.17...Spud keeper 118...
- Stern protruding support part, 19... Main spud as a pivot member, 19a... Arm for connecting spud body, 19b.
・Suha) 'Book (L 20.21'... Trunnion, 22... Wire, 23... Hydraulic sill, A-2 Dredging device as working device 8. Figure 7 Figure 8 Figure 9 Figure 10 Procedure Written amendment - Mr. Kazuo Wakasugi, Commissioner of the Japan Patent Office 1 Indication of the case 1982 Patent Application No. 34857'2 Name of the invention Workboat 3 Person making the amendment Relationship to the case Applicant Postal code 100 Address 96, Chiyoda-ku, Tokyo 2-5-1 Name (620) Mitsubishi Heavy Industries, Ltd. 4 Sub-Agent Postal code 160 Address Odakyu Shinanomachi Apartment Room 706, 5-3 Minamimotomachi, Shinjuku-ku, Tokyo 5 Date of amendment order (voluntary amendment) 6 Amendment 7. Contents of amendment (1) "Small" written in the second line from the bottom on page 18 of the specification was replaced with the following sentence. The bending moment M acting on the cross section of the spud near the lower end of the spud keeper 17 that supports the main spud 1 is also relatively small. (2) "Bending moment" written in lines 5-6 of page 9 of the specification is corrected to "bending moment M'". (3) Add the next sentence on a new line next to "Kataru." written in lines 5 and 6 of page 9 of the specification. ``In addition, the symbol S in Figures 8 and 10 indicates the seabed.'' (4) ``Dredging equipment'' written on the last line of page 17 of the specification I@ is replaced with ``Dredging equipment, M, M'.・Bending moment, S
...undersea. ”. Mr. Kazuo Wakasugi, Commissioner of the Patent Office 1 Indication of the case 1983 - Patent application t53/1.857- No. 2 Name of the invention Work boat 3 Person making the amendment Relationship to the case Applicant postal code 100 Address Chiyoda-ku, Tokyo 2-5-1 Marunouchi Name (620) Mitsubishi Heavy Industries, Ltd. 4 Sub-agent Postal code 160 Address Odakyu Shinanomachi Apartment Room 70'6, 5-3 Minamimotomachi, Shinjuku-ku, Tokyo Date of amendment 6 Amendment Target drawings. 7. Contents of the amendment (1) Figure 8 of the drawing will be amended as shown in the attached sheet. (To delete explanatory characters and add the symbols 1, 1?, S1M.) (2) Figure 10 of the drawing amended as shown in the attached sheet. (To delete explanatory characters and add codes 1.17.S and M'.) Figure 10

Claims (1)

[Claims] A working device is provided at one end of the hull, and a pivot member is provided at the other end via a wire from a tree provided on the hull, and the pivot shaft member penetrates the seabed with its tip. The base end of the arm shaft is a horizontal shaft that rotatably supports the arm shaft. and a drive device that moves the hull relative to the arm shaft, and is attached to the f111 body through a driving device that moves the hull relatively to the arm shaft, and a ground pressure of the swinging tip shaft portion and the wire at the tip of the swinging shaft member. A work boat, characterized in that it is provided with additional weight capable of increasing the tension of the work boat.