CN205632955U - Automatic righting device that topples of single point mooring floating structure thing - Google Patents

Abstract

The overturning self-righting device for a single-point mooring floating structure is characterized in that: it is installed between the floating body and the mooring anchor chain of the floating body; A righting swing arm is installed below, and the righting swing arm is flexibly connected with the support structure. A weight is installed under the righting swing arm, and the bottom of the weight is connected with the mooring anchor chain. The invention has a simple structure and is easy to manufacture and install. It is especially suitable for small-sized single-point mooring marine floating structures, improves the seakeeping performance of the floating body in waves, and realizes automatic righting after the floating body capsizes, ensuring the safety of the device. Safety.

Description

Overturning self-righting device for single point mooring floating structures

technical field

The utility model belongs to the technical field of marine engineering machinery and relates to an anti-overturning structure of an ocean floating body, in particular to an automatic righting device after overturning of a single-point mooring floating structure.

Background technique

Single point mooring floating structure is a general term for a type of marine floating structure. This type of structure usually includes a floating body on the sea surface and an anchor chain for mooring the floating body. The floating body is fixed at a certain point in the ocean by mooring. For example, various data buoys and ship marks for marine environment monitoring, float-type wave energy devices that use wave energy to generate electricity, and navigation lights for ship piloting, etc.

The deck or floating body cabin of this type of structure is usually equipped with various instruments and equipment to achieve specific functions. Taking the marine environment monitoring buoy as an example, the deck of the buoy is usually equipped with miniature antennas, wind direction sensors, temperature and humidity sensors, etc., and the inner cavity of the buoy is equipped with a centralized control center, batteries, generators, etc. Affected by sea conditions, the buoyant body floating on the sea will be subjected to the effects of waves, wind and currents. Although the stability of this type of structure is calculated at the beginning of construction, for example, in order to increase the stability of the floating body, heavy objects are usually installed in the floating body cabin to increase the ballast of the floating body to lower the center of gravity of the floating body and increase the stability of the floating body. However, this structure will occupy the available space in the floating body cabin, and at the same time, it is still possible to capsize under extreme sea conditions or accidental collision of ships, and once capsized, it cannot self-righte, causing losses.

Utility model content

The purpose of this utility model is to provide a self-righting device for a single-point mooring floating structure after overturning. normal working condition.

The technical scheme of the utility model is as follows: the overturning self-righting device of the single-point mooring floating structure is installed between the floating body and the mooring anchor chain of the floating system; it includes a support structure installed on the lower end surface of the floating body and extending below the floating body, A righting swing arm is installed below the supporting structure, and the righting swing arm is flexibly connected with the supporting structure. There is a weight under the righting swing arm, and the bottom of the weight is connected with the mooring anchor chain.

Preferably, the support structure includes a frame structure, and an adapter plate is provided at the bottom of the frame, and the righting swing arm is connected to the adapter plate.

Preferably, the righting swing arm is connected to the supporting structure through a universal joint. The righting swing arm can freely swing and rotate around the universal hinge.

Preferably: the weight is circular and has a small damping coefficient.

Preferably, in the upright floating state, the center of gravity of the floating body system composed of the floating body and the self-righting device is on the same plumb line as the center of buoyancy.

The beneficial effects of the utility model are:

1. Compared with the traditional mooring structure in which the anchor chain is directly installed at the center of the bottom of the floating body, the utility model adds a frame structure at the bottom of the floating body, and the tether point is located at the bottom of the frame, which reduces the position of the mooring point and increases the anchorage. The righting moment enhances the stability of the floating body on the surface.

2. The lower end of the bottom frame of the floating body is connected to the single pendulum structure, and the weight of the single pendulum is used as external ballast, which lowers the position of the center of gravity of the floating body, avoids the inconvenience of configuring ballast in the internal compartment of the floating body, and increases the effective use of space inside the floating body cabin .

3. The bottom of the frame is connected with a single pendulum structure through a universal joint. The single pendulum can swing with the swing of the floating body, which can partially absorb the wave excitation energy borne by the floating body system, and reduce the motion response of the floating body to swing with the waves and heave. Enhance the seakeeping of the floating body.

4. After the mooring floating body capsizes, the single pendulum structure swings to the bottom plane of the frame under the action of gravity. At this time, the center of gravity of the weight is far away from the line of action of the buoyant center of the floating body, and a righting moment is generated. The righting arm GZ in this state is guaranteed by calculation are less than zero, it can ensure that the floating body can return to the positive floating state by itself.

5. The utility model has a simple structure and is easy to manufacture and install. It is especially suitable for use on small-sized single-point mooring marine floating structures, improving the seakeeping performance of the floating body in waves, and realizing automatic righting after the floating body capsizes. Ensure the safety of the device.

Description of drawings

Fig. 1 is the structural representation of the utility model.

Figure 2 is a schematic diagram of the force on the floating body after it is tilted.

Figure 3 is a comparison diagram of the static stability restoring lever curves in the upright floating state before and after the floating body is equipped with an automatic righting device.

Fig. 4 is a schematic diagram of the structural state and force of the utility model after overturning.

Figure 5 is a comparison diagram of the static stability righting arm curves of the overturned state before and after the floating body is equipped with the self-righting device.

Among them: 1-floating body, 2-frame, 3-universal hinge, 4-righting swing arm, 5-weight, 6-mooring anchor chain, 7-floating center of gravity, 8-floating body buoyancy center, 9-transfer plate

detailed description

As shown in Figure 1, the overturning self-righting device for a single-point mooring floating structure is installed between the floating body 1 and the mooring anchor chain 6 of the floating body; Structure, the supporting structure provides the transition function for the floating body and the centralizing device. For the convenience of design and the stability of the structure, the support structure adopts the frame 2 structure, and the frame 2 is made of pipes or profiles, which is a polygonal structure. When the floating body 1 is floating upright, the anchor point of the floating body 1 is lowered.

Below the bottom of the frame 2 there is a structure connecting with the righting swing arm 4, the connecting structure includes an connecting plate 9, the connecting plate 9 is mounted flat and parallel to the direction of the sea surface. The righting swing arm 4 is made of rigid material, which is a metal tube or metal rod, and extends vertically downwards. There is a movable link between the righting swing arm 4 and the adapter plate, and the righting swing arm 4 can be wound around its connection with the adapter plate 9 turn around. In this embodiment, a universal hinge 3 is installed at the adapter plate, and the righting swing arm 4 is connected to the adapter plate 9 through the universal hinge 3. Under the action of waves, the righting swing arm 4 moves freely around the universal hinge 3. Rotate and swing, absorb part of the energy exerted by the waves on the buoyant body 1, and adapt to the excitation of waves in all directions.

There is a weight 5 below the righting swing arm 4, which is an integrated or detachable structure between the weight 5 and the righting swing arm 4, and the bottom of the weight 5 is connected with the mooring anchor chain 6. Heavy block 5 is the cement heavy block of metal or pouring, and in order to reduce drag coefficient, the profile design of heavy block 5 is spherical. Compared with the traditional structure in which the anchor chain is directly connected to the floating body 1, the installation of the weight 5 lowers the center of gravity of the entire floating body system, thereby increasing the stability of the floating body. At the same time, the weight 5 can also absorb part of the waves. The swaying energy reduces the swaying amplitude of the floating body 1 and increases the seakeeping performance of the floating body 1 . On the other hand, the weight 5 replaces the ballast installed in the floating body cabin, increases the effective space inside the floating body cabin, and avoids the inconvenience of disposing the cabin inside the floating body.

The floating body system composed of the floating body 1 and the centralizing device is designed as a symmetrical structure. In the upright floating state, the center of gravity and the center of buoyancy of the floating body system composed of the floating body 1 and the self-righting device are on the same vertical line. This structure is beneficial to increase the stability of the whole floating body system.

The impact of waves on the floating body 1 will only cause the floating body 1 to swing under relatively light conditions, but the floating body 1 still maintains a positive floating state. In this case, the floating state of the floating body system on the sea surface is shown in Figure 2 and Figure 3 Show.

Referring to FIG. 2 , it is a cross section of an inclined floating body 1 . The floating body is inclined at a certain angle φ under the action of the external tilting moment, the position of the center of gravity of the floating body 1 is G, which does not change, and the drainage volume Δ is equal to the weight of the floating body, and does not change. However, due to the change of the position of the waterline, the shape of the displacement volume of the floating body ₁ changes, and the center of buoyancy moves from B to B1. At this time, the center of gravity and the center of buoyancy are no longer on the same vertical line, so buoyancy and gravity form a force couple, that is, the righting moment _MR that prompts the floating body 1 to return to its original equilibrium position. The straight line GZ drawn from the center of gravity G is perpendicular to the vertical line passing through B1, then the expression of the righting moment M _R is as follows:

M _R ＝Δ·GZ

Among them, GZ is the righting arm. The righting arm corresponding to different inclination φ is calculated and drawn as a curve, that is, the static stability curve of the floating body is obtained, as shown in Figure 3. If the direction of the righting moment is opposite to that of the tilting moment, GZ is a positive value, which means that once the tilting external force disappears, it can make the floating body 1 return to the original positive floating balance position. If the direction of the righting moment is the same as that of the tilting moment, then GZ is a negative value, which will prompt the floating body 1 to continue tilting.

It can be seen from Fig. 2 that when the self-righting device is added to the bottom of the floating body 1, the center of gravity of the floating body 1 drops to G1, and the righting arm G1Z1 at this time is larger than the original righting arm GZ, which proves that the floating body 1 has a greater Righting moment, stability is improved. It can be seen from Fig. 3 that, compared with the situation without self-righting device, the righting arm of the floating body system will be greatly increased after adding the automatic floating device.

If the sea conditions are bad, the waves will have a bad impact on the floating body 1, and in severe cases, it will cause the floating body 1 to capsize. In this case, the situation of the floating body 1 system on the sea surface is shown in Figure 4 and Figure 5 .

Referring to Figure 4, when the floating body 1 capsizes under extreme sea conditions or accidental ship collision, due to its own gravity, the swing arm 4 will swing around the universal hinge 3 and lean against the bottom adapter plate 9 of the bottom frame, The distance between the center of gravity of the weight 5 and the centerline of the floating body is approximately the length of the swing arm, so the overall center of gravity 7 of the floating body and the buoyancy center 8 of the floating body are not on the same straight line, and a righting moment M will be formed. Under different combinations of the length of the swing arm 4 and the weight of the weight 5 , the quality parameters of the floating body 1 are different, and the static stability is also different. Select the appropriate length of the swing arm 4 and the weight of the weight 5, and calculate the static stability curve of the floating body 1 in this state. If the restoring arm GZ of the floating body 1 is less than zero within the range of 180°, the floating body 1 can be guaranteed Self-righting can be realized under single pendulum configuration state.

Referring to Fig. 5, taking a disc-type single-point mooring wave power generation device with a diameter of 6m as an example, calculate the stability righting lever curve of the overturned state before and after it is equipped with a self-righting device. The solid line is the righting arm curve of the floating body 1 without self-righting device at the bottom after capsizing. It can be seen from the curve that after the floating body 1 capsizes, the righting arm GZ of the floating body 1 is positive when the roll angle is less than 75°. value, indicating that the floating body 1 has a certain restoring moment within this range, that is, the overturned floating body 1 cannot realize self-righting, and only when the inclination angle of the floating body exceeds 75°, the floating body 1 can return to the upright floating state by itself. However, after the floating body 1 equipped with self-righting device capsizes, its restoring arm GZ is always less than zero within the range of 180°, which means that after the floating body 1 capsizes, its righting moment is in the same direction as the tilting moment, which will prompt the floating body 1 to continue to tilt. It can automatically return to the positive floating state.

Claims (5)

1. the auto-strengthening device that topples of single point mooring's floating structure, it is characterised in that: it is arranged between buoyancy aid and buoyancy aid mooring anchor chain； Including being arranged on buoyancy aid lower surface, the supporting construction extended below buoyancy aid, a righting is installed below described supporting construction Swing arm, is flexibly connected between righting swing arm and supporting construction, has a pouring weight below righting swing arm, with mooring anchor chain below pouring weight It is connected.

2. the auto-strengthening device that topples of single point mooring as claimed in claim 1 floating structure, it is characterised in that: described support is tied Structure includes a frame structure, and base of frame has a keyset, and righting swing arm connects with keyset.

3. the auto-strengthening device that topples of single point mooring as claimed in claim 1 or 2 floating structure, it is characterised in that hold up described in: Just it is hinged by universal between swing arm and supporting construction.

4. the auto-strengthening device that topples of single point mooring as claimed in claim 1 floating structure, it is characterised in that: described pouring weight is Circular.

5. the auto-strengthening device that topples of single point mooring as claimed in claim 1 floating structure, it is characterised in that: under upright condition, The center of gravity of the Floating System that buoyancy aid is constituted with auto-strengthening device and centre of buoyancy are on same plumb line.