SU1733321A1 - Ship deck - Google Patents

Abstract

Usage: shipbuilding, deck construction of dry cargo vessels with cargo hatches. SUMMARY OF THE INVENTION: A ship's deck contains longitudinal 1 and transverse 2 sections arranged to form hatches, hatch covers 3 and stops 4 and 5, which secure the hatch covers 3 in the plane of the deck. Along the perimeter of each hatch cover 3, at least one hatch, one group of longitudinal stops 4 is installed on each of the longitudinal sides of the cover and one group of transverse stops 5 on each of its transverse sides. In the case of all the stops, the stationary gaps between the stops of the hull and the hatch covers are determined from a predetermined range. 1 h. the item of f-ly, 4 ill. 1 YO VJ CO OJ SA YOU je 2

Description

FIELD OF THE INVENTION The invention relates to shipbuilding and relates to the construction of decks of mainly dry cargo vessels with cargo hatches.

The known deck of a dry cargo vessel has cargo hatches, containing longitudinal and transverse sections arranged to form hatches, and hatch covers that serve to ensure the water tightness of cargo hatches, as well as to support deck cargo, such as containers.

This deck creates a vessel with reduced tonnage, due to the inability to place cargo under the transverse sections for which no stowing is used (horizontal movement of cargo under the deck), such as containers. The width of the transverse portions is determined on the basis of the need to resist excessive tilting of the hatch holes caused by the torsion of the hull in the sea state. The lateral portions resist distortion, bending in the plane of the deck. Here, one of the diagonals of the hatch hole is lengthened, and the other is shortened.

To increase the cargo capacity of ships, the transverse sections of the deck tend to be narrower, but at the same time to maintain the required torsional rigidity of the hull, it is necessary to increase the thickness of the outer skin, or to introduce additional hull structures such as second board, etc. This leads to an increase in hull weight. Thus, the traditional design is inherent in the contradiction between the desire to increase the cargo capacity of the vessel and reduce its weight.

Closest to the offer is a ship deck equipped with stops installed at the corners of the hatch holes and diagonally oriented hatch covers, while at least two adjacent stops of each hatch hole are movable until interacting with the corresponding hatch cover. Hatch covers prevent the diagonal of their diagonals. This increases the torsional rigidity of the deck, which makes it possible to reduce the width of its transverse sections and reduce the weight of the hull.

However, in a vessel located midway at the top of the wave, the hull experiences a total bend, while the deck is extended and the stops installed at the corners of the hatch covers tend to disperse with the formation of gaps. Hot expressed

the idea of the inadmissibility of gaps in view of the danger of impact interaction of the stops, studies have shown that this danger does not exist, since deformations

decks while sailing a vessel on rough seas occur relatively slowly, with a period of about ten seconds. As for some abrasion, in this case it does not depend on the presence of gaps. So

In other words, it is not the appearance of gaps that is undesirable, but their increase beyond a certain limit. The increase in clearances leads to the fact that the hatch covers do not resist the skew of the hatch to those

5 until the gaps are again reduced to the required minimum. The real deformations of the deck at the wave bending of the ship are such that, under the action of the greatest bending moments, the device prototype

0 performs the tasks assigned to it only if, in order to prevent the occurrence of gaps, it is performed with automatically controlled extension of the stops, in this case, continuous contact of the stops with the hatch covers is achieved. However, the automatic adjustment of the extension of the stops during the navigation of the vessel requires the installation of hydraulic mechanisms. Firstly, their reliability is insufficient to perform such a crucial function - to maintain the overall strength of the vessel. Secondly, the costs associated with them are high.

Participation in ensuring the overall strength of the vessel, the hatch covers of the prototype are designed to resist only the overall torsion of the hull, while the resistance to the total bend is provided only by body connections, without the hatch covers. Indeed, with a general bend of the vessel, when the stops tend to disperse, hatch covers do not work. However, when the body is in the middle on the bottom of the wave, when the body is deflected, the bast shrinks and the hatch covers are compressed from the stops. Therefore, they must be made sufficiently strong to resist these forces. This leads to an increase in their metal consumption,

0 which reduces the positive effect.

The purpose of the invention is to reduce the metal content and increase the reliability of the vessel. The goal is achieved by the fact that in the deck of a vessel containing longitudinal and

5 and transverse sections located with the formation of a hatch, a hatch cover and stops for fixing the hatch cover in the plane of the deck, installed with a gap relative to the cover, the stops are made of groove-ledge, some of which are fixed on the deck at the longitudinal and transverse sides of the hatch cover , and the response - on the cover. The said gap formed by the stop elements is defined by the relation:

4- (i

(Anonepji +

sg g

+ SI Y (APROD) 2,

where t is the number of sections of closure along the length of the hatch;

S - the same, in width;

g - the total number of sections for closing the hatch;

b - the width of the hatch;

I - the length of the hatch;

d is the diagonal length of the hatch;

(Anonep) i - the gap between the elements in the i-th group of transverse stops;

(Aprod) - the gap between the elements in the j-th group of longitudinal stops;

M - the number of transverse stops hatch:

K - the same, longitudinal stops.

The term longitudinal or transverse stops refers to stops that limit the displacement of the hatch cover relative to the hatch in the abutment point only in the longitudinal direction or only in the transverse direction.

Two longitudinal and two transverse stops are the smallest number of stops in order to ensure that the hatch cover resists to tilt the hatch when the ship's hull is twisted.

It is preferable to arrange the longitudinal stops only on the longitudinal sections of the deck, which ensures the transfer of forces from the interaction with the hatch cover when the hull is twisted directly from the longitudinal sections to the vessel hull. Otherwise, if the longitudinal stops are located in transverse sections, the latter would be loaded for work on bending in the plane of the deck, which is undesirable, since it requires an increase in their strength. Similarly, the transverse stops should be installed in the transverse sections of the deck, then the transverse sections will perceive the load along its axis. It is advisable to install only one stop on each side of the lid because, with a larger number of them, the lugs would be loaded during thermal deformations of the lid.

In order to be able to put the hatch cover in the presence of the initial skew of the hatch caused by the uneven loading of the vessel, or to remove the hatch

the cover in the presence of a residual skew of the hatch hole caused by an uneven distribution of fuel and reserves consumed during the voyage of the vessel, between the elements of the hull and cover stops there should be gaps, the value of which is determined from

one

go

to

one

(Apoper) +

+ SI 2 (APROD1 2 -1SG3, j 1

In this case, the gaps (Apoper) and (Aprod) are determined in the direction of the abutment for covers that are laid without displacement, i.e. these gaps are the same both in the direction there and back.

If the inequality is violated, then the covers will not resist skewing of the hatches even under extreme torsional loads on the ship on rough seas.

FIG. 1 and 2 depict options

the proposed deck for cases of one and two rows of hatches across the width of the vessel, in figs 3 and 4, embodiments of the stops.

The deck contains longitudinal 1 and transverse 2 sections located with the formation of hatches, and hatch covers 3 provided with stops so that for each hatch cover there are two longitudinal stops 4 and two transverse stops 5. Long stops 4 are located on

the longitudinal sections 1, and the transverse stops 5 are installed in the transverse sections 2. The stops 4 and 5 can be made either stationary or with the possibility of selecting gaps, for example by means of a set

mortgage plates or screw mechanism. The stationary stops are made in the form of a combination of one or two pedestals 6 on the body and protrusions 7 on the hatch cover.

The magnitudes of the gaps satisfy the ratio

1µm

- (tb Ј (Apoper) + SI 2 GHA

(AnPofl) j 2,

Indeed the substitution of quantities: m; m; m: (Apoper) s, 4 10 mm; (Apoper) 1 2. 5 3 mm; (Aprod) 3 mm;

gives fair inequality

7 2 - ..

The proposed device in comparison with the prototype provides the following

positive effect; resisting only the torsion of the hull of the vessel, the hatch covers do not experience additional loading during the total bending of the hull. This leads to a decrease in metal intensity of hatch covers; The covers resist the torsion of the body, starting with a certain, predetermined degree of twisting, without using unreliable and expensive automatic devices: hatch covers work under shear conditions, rather than compressing along the diagonals, as a prototype. Since the shear stiffness of hatch covers is greater than the stiffness under diagonal compression, it is possible to obtain the required stiffness with a smaller mass of hatch cover design, which leads to a further decrease in their metal intensity.

Claims (1)

Claim 1. Deck of the vessel, containing longitudinal and transverse sections arranged to form a hatch, hatch cover and stops for fixing the hatch cover in the plane of the deck, installed with a clearance relative to the cover, characterized in that, in order to reduce the metal intensity and increase the reliability of the vessel , the stops are made of elements like groove the ledge, some of which are fixed on the deck at the longitudinal and transverse sides of the hatch cover, and the response - on the cover. 2, the deck of claim 1, wherein the gaps between the stops fixed on the deck of the vessel and the stops on the hatch covers for the hatch under consideration are determined from the range 1i - ± - (tb 2 (Anonep) i + d2 r i i + SI Ј (APROD) 2, I 1 where t is the number of sections of closure along the length of the hatch; S - the same, in width; g - the total number of sections for closing the hatch; b - the width of the hatch; I is the length of the hatch; d is the diagonal length of the hatch; (Apoper) - the gap in the i-th group of transverse stops; (Aprod) clearance in the j-th group of longitudinal stops; M is the number of transverse stop groups for a given hatch; K - the same, longitudinal stops. four/ // figure 1 fig J fae. four