JPS6015286A - Ladder type working ship - Google Patents

Abstract

PURPOSE:To secure exact operations of a ladder type working ship by lessening the resistance of tidal current by a method in which front and rear pontoons are connected with a girder on the water surface, a vertically movable spud and a rocking ladder for working are provided to the rear pontoon, and the hanging rope of the ladder is coupled to the girder. CONSTITUTION:A front pontoon 15 and a rear pontoon 16 are connected with a girder 17 on the water surface. Vertically movable spuds 20 and 21 are provided to the back end of the rear pontoon 16, and a ladder 4 for seabed working is pivotally attached to the front end of the pontoon 16 through a trunnion 3 in a rocking manner. The other end of the rope of the ladder 4 is coupled to the winch 19 of the girder 17. By such a hull structure connected with the rear pontoon, the portion to be immersed into water of the hull can be lessened, the resistance of tidal current can be reduced, and therefore, exact operations can be secured even in the rough weather period.

Description

[Detailed Description of the Invention] The present invention relates to a work boat equipped with a ladder for undersea work,
In particular, it relates to a rudder-equipped work boat that can work even in waves.

As a work vessel equipped with a conventional submarine work ladder, there is a canter-suction dredger as shown in Figure 1.
A rudder well 2 is formed at the front of the hull 1, and the base of a suction rudder 4 is pivoted to the rudder 1-well 2 via a trunnion 3. A force transition 5 is provided at the tip of the suction lug 1.

In such a conventional work boat with a rudder, the cutter head 5 is located far away from the center of gravity of the mouth 1), so if the hull 1 is hit by longitudinal waves or oblique waves, the cutter head 5 will move up and down considerably. upset. (See Figure 2) Therefore, with such conventional rudder-equipped work boats, there is a problem that dredging work becomes difficult in undulating waters or in waves, and the operating rate decreases.

In addition, since the cutter head 5 is provided protruding from the hull 1, inspection and repair work must be carried out on the sea surface, which is time-consuming and dangerous during waves. There is also.

In order to solve these problems, an improved rudder-equipped work boat as shown in Figs. 3 and 4 has been devised. That is,
A rudder well 2 is shaped like an extension of the hull 1 and surrounds the entire lug 4. - In this improved rudder-equipped work boat, the length of the hull 1 has been increased to reduce the amount of movement of the hull 1, and the cutter head 5 has been lowered when the rudder 1 is lowered to the seabed 7. Since the distance 11 in the captain's direction between and the center of gravity 1 ( ) of fleet 1 becomes smaller (see Figure 7), lli,i
The -1-downward movement of the canterhead 5 due to the movement of the tree 1 decreases. (See Fig. 5) Furthermore, when the cutter head 5 is placed on the sea surface 6-1- to perform inspection or repair, the work can be carried out on the hull 1, so it is possible to carry out inspections and repairs during the waves. You can also work safely.

However, in the improved rudder set working port () in which the body 1 is extended, the lateral area of the hull 1 below the water surface 6 increases, so the tidal current force in the width direction that the hull 1 receives increases.

Then, the center of gravity 1 () of J, sea urchin, and li body 1 shown in Fig. 7
The component ρ2 in the longitudinal direction of Mli distance between the center of gravity 10' of rudder/1 and the center of gravity 10' of the rudder/1 is the distance ρ1 between the center of gravity 10 of the hull 1 and the spant 12.
41 is always smaller than that of the conventional example described above, the swing wire 11 supports most of the tidal current force, and the tension acting on the swing wire 13- is 2.5 times smaller than that of the conventional example described above.
~3 (S) (see FIG. 6) Therefore, the swing winch (not shown) for winding the swing wire 11 needs to have a large capacity.

In addition, as shown in Figure 8, check the cutter at 7F.
For repairs, etc., one ladder 11 was installed on the water surface 6-. When the swing wire 1 is lifted, it comes into contact with the swing wire 1 and the hull 1, causing the wire to break.

In order to avoid this, when suspending the rudder 4, the swing wire 11 is loosened and another mooring wire is provided to suspend the rudder 4.
There is also the problem that the equipment becomes large-scale and the work becomes complicated.

The present invention aims to solve the problems mentioned in J.
By reducing the downward motion of the canterhead caused by waves and by reducing the force acting on the hull in the transverse direction, the tension acting on the swing wire is reduced, and the tension on the cutter/drive is reduced. The inspection and repair work can be carried out easily 4- It is decided that a work boat with a complete rudder will be delivered.

For this reason, the rudder-equipped work boat of the present invention has a hull in which the front pontoon and the rear pontoon are connected by a gargoo in the water surface, and a rear end of the rear pontoon that can be raised and lowered. A hull swinging mechanism is provided, comprising a spud and a subsea working ladder pivotally attached to the front end of the rear pontoon via a trunnion, and swinging the hull together with the rudder about the -1- subband. 1. ■ Symptom.

Hereinafter, according to the drawings I) A working boat with a rudder set as an embodiment of the present invention will be explained. Fig. 9 is a side view thereof, and Fig. 1
Figure 0 is a plan view of the same, showing the curved pontoon 15 and the rear pontoon 16 on a girder 1 installed at the water surface 6''.
7 to form the hull.

At the rear end of the rear pontoon 16, a main spud 20 and an auxiliary spud l'21 are provided so that they can be lowered under severe sea conditions. A Christmas tree one-way wire mooring 5-device 22 is provided which is used in place of the auxiliary spud 21.

The submarine work ladder 4 connects its base to the rear pontoon 16.
is pivotally attached to the front end of the Boogoo 1 via a trunnion 3, and is raised and lowered so as to rotate around the trunnion 3 by a winch 19 provided on the Boogoo 1f.

And main spant 20. A swing wire 11 and a winch (not shown) are provided as a hull swing mechanism for swinging the hull together with the rudder 4 around the auxiliary spud 21 or the Christmas tree one-way wire mooring device 22.

In addition, the code|symbol 23 in a figure has shown the control room, the code|symbol 24 has shown the engine room, and the code|symbol 25 has shown the pump room.

Even with the above-described configuration, dredging work can be performed in the same manner as in the conventional example.

That is, by swinging the hull and rudder 4 around the main spud 20 or the auxiliary spud 21, and by switching the center between the main spud 20 and the auxiliary spud 21, the rudder 11 moves forward or backward. The dredging work is carried out by means of a canter (5) cut into the tip of the canter.

In addition, in the same manner as in the conventional example of the improved type mentioned above, the canter that is attached to the oscillation of the hull/).
a.

Furthermore, in this embodiment, since the pontoon 15 is divided into the rear pontoon 15 and the rear pontoon 1, the side area of the hull at the water surface 6F is reduced, and the submerged part of the hull 1ljj Since the ratio of the length in the bow direction to the length in the transverse direction decreases, the tidal current resistance to which the hull is subjected decreases, and the force acting on the swing wire 11 and the tip of the rudder 11 decreases.

In addition, since the girder 17 is placed above the water surface G,
Even when the rudder 11 is suspended on the water surface 6I-, the swing wire 11 does not come into contact with the hull, and no separate mooring wire is needed for the rudder 4 to be suspended.

In addition, since the submerged part of the hull is only at the rear of the curve, there is no significant vertical bending moment in the hull during waves, and the inside of the girder 17 is also effective as a living space. -7= It also has the advantage of reducing the weight of the entire ship's steel material.

As described in detail below, the rudder-equipped work boat of the present invention has a hull in which the front pontoon and the rear i'fls pontoon are connected by force above the water surface, and -1-
The rear bontoon is equipped with a spud that can be raised and lowered at the rear end of the rear bontoon, and -1- the front end of the rear bontoon @l (t: I). It has a simple structure in which a hull swing mechanism is installed that swings the rudder and the spud around the spud, and as the vertical movement of the rudder during waves is small, work can be carried out reliably even during waves, and the hull is able to handle the tidal currents that the hull receives. Since the force is replaced, the swing wire can be easily manipulated, and the Cτ1 band equipment, such as a winch for winding the swing wire, can be simplified.

[Brief explanation of drawings]

Figures 1 to 8 show a conventional rudder-equipped work boat.
The figure is a plan view of a conventional example in which the rudder is attached to the end of the hull.
Figure 2 is a graph showing the downward movement of the cutter head during waves in a conventional example, and Figure 3 is a plan view of an improved example with the rudder located in the center of the hull. , FIG. 4 is a side view showing the working condition, and FIG. 5 is a graph showing -1-downward movement of the cutter head during waves in the improved example.
FIG. 6 is a side view showing the working condition of the conventional example, and FIG. 7 is a side view showing the working condition of the improved example. Figure 8 is a cross-sectional view of the hull when the rudder is suspended in the improved example;
The figures show a working boat with a rudder set as an embodiment of the present invention, FIG. 9 is a side view 1, and FIG. 10 is a plan view thereof. 2... Rudder well, 3... Trunnion, 4... Rudder, 5... Cutter head, 6... Sea level, 7... Seabed surface, 11... Swing wire, 15... Front pontoon,
]6... Rear pontoon, 17... Girder, 11]
・Winch, 20・・Main spud, 21・・Auxiliary spud, 22・・Christmas tree one-way wire mooring device, 2
3...control room, 271...engine room, 25...pump room. Sub-Agent Patent Attorney Yoshihiko Iinuma 9- Figure 1 Figure 2 Figure 4 JflN4

Claims (1)

[Claims] A hull in which a front pontoon and a rear pontoon are connected by a gargoo toward the water surface; A rudder-equipped work boat, which is equipped with a rudder for undersea work, and is equipped with a hull swing mechanism that swings the hull together with the rudder around the subband (-1). .