RU2276037C2 - Ice-breaker ship - Google Patents

Abstract

FIELD: the invention refers to shipbuilding particularly to ice-breaker ships.

SUBSTANCE: an ice-breaker ship has an above-water part which includes a control system, a milling cutters' drive, a passengers' mess; an underwater part which includes compartments for air, fuel, a propulsor; two lateral parts which have a communication system, a hydraulic drive for displacement in the vertical plane of the above-water part relatively to the underwater part and having at the front wedges for cutting-in and breaking ice. The front construction of the upper and the underwater parts are designed in such a manner that the ice plate getting between them is destroyed from arising stress of the bend.

EFFECT: increases speed of a ship's passage through the water area covered with ice at relative reducing of energy consumption for breaking ice.

1 cl, 4 dwg

Description

The invention relates to shipbuilding, in particular to icebreaking ships that destroy ice mechanically.

A device is known (1. Bogorodsky V.V., Gavrilo V.P., Nedoshivin O.A. Ice destruction. Methods, technical means. L .: Gidrometeoizdat, 1983. 232 p. 49 Ice-cutter designed by US specialists) , which is a pontoon with a straight bow, where vertical cutters are installed, "which, when the vessel moves, cut three longitudinal slots in the ice field, resulting in the formation of two cantilever beams" that break down the inclined part of the bottom. Broken ice passes under the hull and is bred under the edge of undisturbed ice due to the V-shape of the keel. Thus, the device reserves a channel clear of ice.

The disadvantages of the known device is the low speed of their advancement in ice [1] due to the low efficiency of the use of mills for the destruction of the ice field. In addition, it is doubtful the unimpeded movement of ice of large thickness (up to 1 m) under the hull of the vessel and its removal under the edge of the undisturbed ice cover.

The task of the invention is to ensure the advancement of an icebreaking vessel in an aqueous environment covered with an ice crust up to 1 m thick at a speed of up to 30 km / h.

The technical result achieved in solving the problem is to increase the speed of the vessel through the water covered by ice, with a relative reduction in energy consumption for ice destruction, prolonged navigation in the spring and autumn season.

The desired result is achieved by developing a device that breaks ice at the least resistance and allows broken ice plates inside its structure.

The essential features characterizing the invention.

Restrictive: an icebreaking vessel, the hull of which consists of a surface part, an underwater part and two side parts, and is equipped with an ice breaking device containing cutters mounted vertically.

Distinctive: between the indicated parts of the hull there is a cavity designed for the vessel to move through the ice cover, while the surface part is made to move in a vertical plane relative to the underwater part, the width of the underwater part of the vessel exceeds the width of the surface part and has a bend in the terminal part for contact with the underwater ice surface, milling cutters mounted on the lower surface of the surface of the surface and the side surfaces have the ability to rotate, the surface of the surface in its nasal region the tee is made inclined and equipped with cutters, the underwater part is also equipped with a cutter mounted in the bow area, the side parts are additionally provided with wedges, while the side parts are narrowed to the stern on the outside and expand on the inside, while moving the surface of the vessel relative to the underwater is carried out using a hydraulic actuator mounted on the side parts, while the height h between the surface and underwater parts is selected from the calculation h≥1,5S, where S is the thickness of the ice, while the angle of inclination of the surface part and α = 30-45 °, while the angle of narrowing of the side parts from the outside γ = 1-2 °, and the angle of expansion from the inside β = 2-3 °, while the distance between the axes of the cutters mounted on the surface and underwater parts , L = 4-6 meters.

A causal relationship between the set of essential features of the claimed device and a sufficient technical result is as follows.

The presence of a cavity between the surface, underwater and side parts of the device makes it possible to pass broken pieces of ice through the vessel without spending energy on their separation in the ice field. Ice breaking is carried out from bending to the limit of destruction of the ice plate falling into the target between the inclined upper and lower parts of the vessel during its movement. It is known that the least tensile strength is exerted by stresses arising in ice during bending (2. Bogorodsky VV, Gavrilo VP Ice. Physical properties. Modern methods of glaciology. L .: Gidrometeoizdat, 1980). The wedges of the lateral parts cleave the remnants of the undamaged sections of ice for passage of crushed ice along the inner cavity of the vessel.

The underwater part of the vessel, which has compartments with air much wider than the surface to give the vessel a little draft, has a bend in the terminal part for contact with the underwater surface of the ice. The surface of the vessel in front of the underwater surface is inclined to a horizontal plane to create a bending moment in the ice plate located in the alignment between the upper and lower parts, leading to the destruction of ice in the transverse direction relative to the course of the vessel.

To create the most favorable conditions for the destruction of ice in the longitudinal direction in the underwater part in the front in the center and in the surface part in the area of contact of the ice plate there are cutters, and the cutter in the lower part creates a recessed cut in the plate when the vessel is moving, which is a stress concentrator during bending. Cutters on the surface also contribute to the destruction of the ice plate in the longitudinal direction.

For the best passage of ice in the inner cavity at the bottom of the underwater part there is a system of cutters, the rotation of which pushes the ice through the cavity, destroys the broken plates and accelerates the forward movement of the vessel.

The lateral parts of the vessel limit the cavity along which the broken ice passes and have a hydraulic cylinder system that allows you to adjust the height of the cavity by moving in the vertical plane of the surface of the vessel relative to the underwater. In addition, the side parts of the vessel in the area of wedge formation have vertical cutters, the rotation of which facilitates the advance of the vessel and prevents the vessel from jamming from the sides with an ice field. The narrowing of the side parts to the stern from the outside also helps to prevent jamming of the vessel from the sides, the expansion of the side parts to the stern from the inside contributes to a more free passage of broken ice through the inner cavity.

Figure 1-3 shows the design of the claimed device.

Figure 1 is a longitudinal vertical section along the axis of symmetry; figure 2 is a top view along arrow A, figure 3 is a section 1-1 of figure 2.

The device in figures 1-3 consists of a surface part 1, an underwater part 2 and two side parts 3. The surface part in the bow region below is made with an angle of inclination α and has cutters 4, as well as a system of cutters 5 along the entire lower surface, the underwater part has a cutter in front 6. The lateral parts contain wedges 7 and vertical cutters 8. The distance between the surface and underwater parts (h) between the upper and lower parts should be h≥1.5S, where S is the thickness of the ice cover. This value is set by the system of hydraulic cylinders installed in the side parts. To realize the transverse fracture of the ice, it is necessary that the distance (l) between the axis of the cutters of the surface part and the cutter of the underwater part be l = 4 ÷ 6 meters.

The lateral parts are made with narrowing to the stern on the outside at an angle γ = 1-2 ° and expansion at an angle β = 2-3 ° with the inside.

The operation of the device is as follows.

On a vessel in clear water (lane), using the hydraulic cylinders and air sections of the underwater part, the height of the tunnel and sediment is established depending on the thickness of the ice. The engine and drive of all cutters are turned on. An icebreaking vessel picks up the required speed and finds on the ice cover. When the vessel moves, the ice plate, abutting into the inclined surface of the surface part, under the action of the vertical force arising on the inclined surface, bends, which prevents the front end of the underwater part. There is a bending moment, under the action of which a transverse kink occurs, which is stimulated by the cutters of the surface and underwater parts. An ice plate (s) under the action of an ice field approaching in front is pushed into a tunnel formed by the surface, underwater and side parts of the vessel and emerges from the stern after passing the vessel. With transverse destruction, protrusions formed in the ice field that impede the movement of the vessel and the passage of ice through the tunnel are chipped off by wedges of the side parts. To prevent the formation of a plug inside the cavity, the distance between the surface and underwater parts exceeds the ice thickness by 1.5 times, and rotating cutters 5 do not allow the ice to slow down on the lower surface of the surface, stimulate further destruction of the ice plates and, pushing away from them, facilitate movement ship forward. The expansion of the tunnel to the stern at an angle β = 2-3 ° also contributes to a more free movement of ice in the tunnel. The movement of ice on the tunnel itself is very relative. In fact, an icebreaking vessel passes crushed ice inside itself, trying to prevent the ice floes from delaying its movement. From the outside, the rotating cutters 8 and the narrowing of the side parts to the stern at an angle γ = 1-2 ° prevent the ship from jamming from the outside of the ice field.

Calculation confirming the achievement of the specified technical result.

The bend of the ice plate between the inclined surface and underwater parts can well be formalized as the bend of the beam in the embedment (Figure 4). The force with which the inclined surface of the surface abuts against the ice plate is the ship's inertia (F). The vertical component of this force will be

Bending moment

The maximum bending moment (M _max ) will be at α = 45 °

Inertia force

where P is the weight of the vessel, a is the acceleration of deceleration, q is the acceleration of gravity (q = 10 m / s ² ).

Bending stress σ _and

W _z is the moment of resistance relative to the z axis. In our case

Then

A kink occurs when σ _and > σ _dop , σ _dop is the permissible bending stress.

Thus, we have

From here we find the weight of the vessel P

If we put the speed of the vessel v = 30 km / h, and the stopping time τ put 3 seconds, then

From [2]

Put b = 10 m, S = 0.5 m, l = 5 m, then we get P> 60 tons.

At the same time, we did not take into account the power of the engine pushing the vessel forward. Thus, if you take P = 100 tons, then you can freely walk in the water with an ice thickness of 0.5 m at a speed of 30 km / h.

Claims (2)

1. Icebreaking vessel, the hull of which consists of a surface part, an underwater part and two side parts and is equipped with a device for breaking ice, containing cutters mounted vertically, characterized in that a cavity is formed between these parts of the hull for the vessel to move through the ice sheet, while the surface part is arranged to move in a vertical plane relative to the underwater part, and the width of the underwater part exceeds the width of the surface part, milling cutters mounted on the lower surface the surface part and on the side parts have the ability to rotate, the surface part in its nose region is inclined and provided with cutters, the underwater part is also provided with a cutter mounted in the nose region. 2. Icebreaking ship according to claim 1, characterized in that the movement of the surface of the vessel relative to the underwater is carried out using a hydraulic actuator mounted on the side parts.

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