JPS5929584A - Mooring device - Google Patents

Abstract

PURPOSE:To reduce the transference of a ship due to external forces and the capability required of a winch, by fitting a floating body to an intermediate part of a mooring line in a partically submerged condition. CONSTITUTION:A floating body 8 is fitted, in a partially submerged condition, to the intermediate part of mooring line 7 fitted between a ship 1 and the bollard 5 on a quay, and sea water is introduced into the floating body 8 through a water intake valve 13. Accordingly, since the transference of the ship 1 due to winds or tidal currents during mooring is reduced, the capability of a winch 6 required for returning the ship 1 to the original position can be redued, and an automatic tensioning mechanism is unnecessitated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention primarily relates to a mooring device for a roll-on/roll-off ship.

As shown in the schematic plan view in Figure 1, the roll-on/roll-off ship is moored with the stern 1a of the hull 1 facing the quay 2, and a rampway 3 is stretched between the stern 1a and the quay 2, and the ship is moored onto a bogie. The 6D ship carries loaded cargo in and out via rampway 3, and is known as a cargo ship convenient for transporting heavy goods.

By the way, when mooring such a roll-on/roll-off ship to a quay, a large number of mooring lines 4a + 4b are required to secure the ship against the effects of wind and tidal currents.
, 4 c, etc., with the bollard 5' installed on the quay 2,
It had to be stretched between the winch 6' provided on the hull 1. Therefore, in the past, when trying to reduce the number of mooring lines used, it was necessary to use cables with a large diameter, which required a powerful winch.

FIG. 2 is a schematic side view showing a conventional mooring system, in which a mooring line 4 is stretched between a bollard 5' on a quay 2 and a winch 6' on a hull 1 with an initial tension F1. . Hull 1 is at the position shown in the two-point chain due to wind and tidal currents by ΔX1
When the mooring line has moved to a distance of , the mooring line becomes in a state of 4' with tension F2.

Therefore, the slack δ between the mooring line 4' and the initial tension F1.

In order to absorb the increased tension F2 and return the hull 1 to its original position, the hull 1 must be equipped with a large-capacity winch 6' that can overcome the increased tension F2 and wind the mooring line. There were many operational and economical problems, such as the need to stretch multiple mooring lines.

From the above-mentioned viewpoints, this invention enables the use of large-diameter mooring lines without requiring a large-capacity winch installed on the ship's hull, and therefore reduces the number of mooring lines. Workability and economy This system provides a highly flexible mooring device in which a floating body is suspended half-submerged in the sea between a mooring line strung between a winch installed on the ship's hull and a bollard installed on the quay. It has particular characteristics.

Next, the present invention will be explained based on examples and drawings.

FIG. 3 is an explanatory diagram showing the mooring device of the present invention. In the device of this invention, the mooring line 7 is connected to the winch 6 of the hull 1.
The mooring line 7 is pulled in and stretched between the bollard 10 on the ship's hull and the bollard 5 on the quay 2, and the floating body 8 is attached to the upper surface of the mooring line 7 using a fitting 9 so that it is half submerged in the sea. Hang it.

The distance 4 and the distance 12 to the bollard 5 are approximately equal to each other. Next, the floating body 8 is fixed at the position of the mooring line 7 by a clamp 12 provided on its upper surface.

Therefore, after the mooring line 7 is stretched with the same initial tension F1 as before, if the hull l is affected by wind force or tidal current,
The mooring line becomes in the state 7' with tension F2, and the floating body 8 also moves to the center position of the mooring line 7'.

At this time, the slack δ between the mooring line 7' and the initial tension F1
2 is the conventional slack δ due to the floating body 8 shown in FIG.

Therefore, the moving distance Δn of the hull 1 is smaller than the conventional moving distance Jx+ shown in FIG.

Therefore, in order to absorb the above-mentioned slack δ2 and return the hull 1 to its original position, there is no need to wind up the mooring line using a large-capacity whip like in the past. That is, according to this system, a mooring line with a large diameter can be used regardless of the capacity of the installed winch, and the diameter of the mooring line and the diameter of the floating body can be selected depending on the external force acting on the ship.

Note that the floating body 8 moves up and down depending on the tension applied to the mooring line 7, but the amount of this up and down movement is small, and the moving distance of the hull 1 is 7.
．． The influence on Δ and X2 can be ignored.

In addition, the mooring line is a floating body 8 stretched on the bow side as shown in Figure 4.
It is sufficient to use only the mooring lines 7a, 7a on which the mooring lines are suspended, and the mooring lines 7b, 7b stretched on the stern side.

Next, the mooring state by the device of this invention is shown in FIGS. 5 to 7.
This will be explained using figures. That is, as shown in FIG. 5, the mooring line 7 is passed through the floating body 8, the winch 6 is wound around the mooring line 7, and the floating body 8 is set approximately in the center of the mooring line 7.
At the same time, the floating body 8 is fixed to the mooring line 7. At this time, the downward force of the floating body 8 is W+, and the height of the floating body 8 above the water surface is W+. , the initial deflection of the mooring line 7 is δ'.

Next, as shown in FIG. 6, by opening the water injection pulp 13 provided on the bottom surface of the floating body 8 and injecting a predetermined amount of water into the floating body 8, the downward force of the floating body 8 is reduced to W2, It is assumed that the height is hl and the initial deflection of the mooring line 7 is smaller than the above-mentioned δ'. At this time, the mooring line 7 is connected to the bollard 10.
Since it is fixed to , no force is applied to the winch 6.

In this state, as shown in Figure 7, the hull 1 is moved by an external force.
When the floating body 8 moves by ΔX, the floating body 8 is lifted by Δh. The downward force on the floating body 8 at this time is Δ”W = W3-W2
=, Δ, hAγ (where A is the cross-sectional area of the floating body, 5, and γ is the specific gravity of water). This Δh is a very small displacement that provides a downward force equal to the upward increase in F2.

As described above, according to the present invention, the hull.

When mooring lines are strung between the winch installed on the ship's hull and the bollard installed on the quay, the winch has a small capacity and does not require an auto-tension mechanism.
And it can be done easily and reliably with a small number of mooring lines1.
Excellent operational and economical effects are brought about.

[Brief explanation of drawings]

Fig. 1 is a schematic plan view showing a conventional mooring state, Fig. 2 is a schematic side view showing a conventional mooring device, Fig. 3 is a schematic side view showing a mooring device of the present invention, and Fig. 4 is a schematic side view showing the mooring device of the present invention. FIGS. 5 to 7 are explanatory diagrams showing the moored state of the device according to the present invention. In the drawings: 1. Hull, 2. Quay, 3. Rampway, 4.
... Conventional mooring line, 5, 5'... Bollard, 6
．． 6'...Winch, 7...Mooring rope, 8...Floating body, 9...Mounting with metal fittings. lO... Hull bollard, 11... Mooring pipe, 12... Clamp, 13... Pulp for water injection. Applicant Nippon Kokan Co., Ltd. Agent Natsuo Shioya (and 2 others)

Claims (1)

[Claims] A mooring device characterized by a floating body suspended half-submerged in the sea in the middle of a mooring line stretched between a winch installed on the hull and a bollard installed on the quay.