CN102762444B

CN102762444B - A shallow water system

Info

Publication number: CN102762444B
Application number: CN201080064066.7A
Authority: CN
Inventors: C·D·克里斯坦森
Original assignee: Its People's Oil Well Hua Gao Denmark Co
Current assignee: Its People's Oil Well Hua Gao Denmark Co
Priority date: 2009-12-16
Filing date: 2010-11-26
Publication date: 2015-03-11
Anticipated expiration: 2030-11-26
Also published as: AU2010333428B2; EP2512911B1; AU2010333428A1; BR112012014650A2; CN102762444A; IN2012DN05149A; EP2512911A1; WO2011072687A1; BR112012014650B1; MY158414A; EP2512911A4

Abstract

The invention relates to a shallow water system comprising a floating weathervaning vessel (3) with a topside hang-off structure, a subsea structure and at least one flexible transporting unit (2) extending from the topside hang-off structure to the subsea structure (1). The weathervaning vessel (3) has a bow with a lowermost bow midpoint. The weathervaning vessel is moored such that at still water it can weathervane around a weathervaning vertical centre line, such that the position of the lowermost bow midpoint follows an annular lowermost bow line which defines a vertical tube shaped border to a lowermost bow midpoint exclusion zone (LE-zone). The subsea structure (1) is arranged in said LE-zone. The weathervaning vertical centre line (9) is preferably the nominal weathervaning vertical centre line. The weathervaning vessel (3) is generally a line moored weathervaning vessel. The shallow water system of the invention provides a simple system for design with a high safety against damaging of flexible transporting unit (2). The shallow water system is in particular beneficial for use at very shallow water.

Description

Shallow Water System

Technical field

The present invention relates to Shallow Water System, this Shallow Water System comprises floating weathercock ship, submarine structure and one or more flexible delivery unit extended between.

Background technology

Shallow Water System involved in the present invention is well known in the art, and is generally used for other medium carried fluid, electric power, electromagnetic wave and be sent to or come self-relocation weathercock ship.

The weathercock ship that floats comprises outside turret system or internal turret system usually, and one or more flexible delivery unit proceeds to submarine structure from this floating weathercock ship.This flexible delivery unit of internal turret System guides is through hull bottom, and outside turret system guides flexible delivery unit to extend across hull and boats and ships fence from top side suspended structure.The present invention be more particularly directed to comprise outside turret system or other similar Shallow Water System for the mooring system by lashing grappling weathercock ship.

The usual mooring of weathercock ship to sea bed, but under specific circumstances also can by lashing by mooring to one or more fixed sturcture.By the mooring of weathercock ship, thus can move with the wind around vertical line of centers, make this weathercock gear have very large freedom of motion to carry out adaptations as being applied to the power on this weathercock ship by wind, current and wave simultaneously.Weathercock ship can such as relatively nominal position (peri position) and (amphi position) motion backward forward, and this nominal position is defined as position when namely weathercock ship is not subject to that such as wind, current, wave etc. affect by weather effect.

In shallow water area, weather condition has extreme influence to motion of ship, even if weathercock ship is by mooring, the motion of this weathercock ship also may become very violent.

US Patent No. 2004/0028477 describes a kind of system, this system comprise there is top side suspended structure weathercock ship, submarine structure and at least one extend to the flexible delivery unit of this submarine structure from this top side suspended structure.In order to ensure that weathercock ship can not collide with submarine structure, even if the vertex of this submarine structure also needed far below hull bottom in the low water time.This length will seriously restricting supply unit when system is positioned at shallow water area and can have.

In order to make set flexible delivery unit, there is enough length to move under weather effect to allow weathercock ship, Shallow Water System of the prior art is usually built into and makes flexible delivery cell layout waviness configuration, such as serpentine configuration or the similar waveform configuration such as described in US Patent No. 4793737.

In this waveform configuration, flexible delivery unit by support unit if fixing sea bed structure example is if Intermediate Water Depth's bow member or Intermediate Water Depth's stent support are at distance seabed one segment distance.

Term " sea bed " is generally used for representing ground, seabed.

For guaranteeing that support unit does not collide with it when weathercock shipping is moved, the support unit of Shallow Water System of the prior art has the mode of safety zone to arrange according to below weathercock ship bottommost.Calculate this safety zone relatively with the expection predicted motion of weathercock ship when standing extreme weather conditions, usually based on certain time scope as the known weather condition in past 20 years or 100 years.The safety zone of 2-20 rice is much.

As mentioned above, the waveform configuration of flexible delivery unit makes flexible delivery unit have one section of redundant length relative to the top side suspended structure in weathercock ship nominal position to the distance between submarine structure.But, due to the motion under weather condition impact of weathercock ship, so for specific Shallow Water System, the distance between top side suspended structure and submarine structure may change a lot.This may cause flexible delivery unit to be excessively bent or contacts to earth and pull on sea bed, and/or flexible delivery unit may be stretched, and this stretching may cause flexible delivery unit to damage.

The object of this invention is to provide a kind of Shallow Water System, this system forms better protection to flexible delivery unit, is easy to design with the safety margin of hope and arrange simultaneously.

Summary of the invention

The Shallow Water System that object of the present invention is limited by claim realizes.Other advantageous scheme may with other advantage limits in the dependent claims and is described below.

Shallow Water System of the present invention comprises floating weathercock ship, float weathercock gear have top side suspended structure, submarine structure and at least one extend to the flexible delivery unit of submarine structure from top side suspended structure.

" float weathercock ship " or only " weathercock ship " represent a kind of boats and ships, these boats and ships pass through lashing mooring to sea bed and/or to one or more fixed sturcture, thus rotate completely or part rotation around vertical line of centers under the impact that also can be current, wind and wave at weather.As a rule, weathercock ship will by the direct mooring of multiple mooring lashings to sea bed.Weathercock ship such as can rotate, thus can be positioned at the optimum position of apparent wind, current and/or wave, to keep stable as far as possible on the water surface.In one embodiment, weathercock ship and mooring structure thereof are configured to make weathercock ship all the time windward.

The weathercock ship that vertical line of centers (being also referred to as the vertical line of centers of weathercock) is defined as mooring on hydrostatic with the wind motion around vertical axis, and when moving with the wind, the distance between weathercock ship with this vertical axis is equal all the time.The vertical line of centers of nominal is limited by weathercock ship when being positioned at nominal position.Weathercock ship is not being exactly its nominal position by position during the affecting of any power produced by weather condition (wind, current and wave).When weathercock accommodation is in its nominal position, this weathercock ship can move with the wind around vertical axis and other motion any not occur, and this vertical axis extends to the vertical line of centers-sea bed point of sea bed.Vertical axis is herein defined as the vertical line of centers of nominal (being also referred to as the vertical line of centers of weathercock nominal), line of centers-sea bed point is the point cut out by the vertical line of centers of nominal, and this line of centers sea bed point can be used to represent the position of the vertical line of centers of nominal.Vertical nominal centerline can calculate after weathercock ship is by mooring.

Weathercock ship can be the weathercock ship that any one has outside turret system or other similar mooring system.The example of weathercock ship comprises FPSO (production of floating, storage and uninstalling system), FSO (floating storage and uninstalling system) and FSRU (floating storage and regasification unit system).

Top side suspended structure is that flexible delivery unit or multiple flexible delivery unit connect and from weathercock ship hangs structure.In this article, top side suspended structure is defined as the point of connection that riser is connected to sea boats and ships.Top side suspended structure can have arbitrary size and dimension.This top side suspended structure is well-known in the art.

Flexible delivery unit can be that any one is for the flexible delivery unit in this Shallow Water System.Flexible delivery unit can be such as flexible risers or umbilical cables.Preferably, Shallow Water System comprises multiple flexible delivery unit, such as, comprise many risers, as comprised many risers and comprising at least one umbilical cables alternatively.Flexible delivery unit-sometimes also referred to as cross-over connection pipeline-as riser and umbilical cables be all well known in the art.Riser is usually applied to and petrochemical is delivered to surface facility as weathercock ship from sea bed.Umbilical cables through be usually used in toward and/or from sea bed or above sea bed facility conveying fluid, electric power, signal and other.

Weathercock gear has hull, and this hull has fore and minimum fore mid point.Fore is weathercock bow region, and fore mid point is line fore being divided into substantially equal two halves.

Weathercock ship is become this weathercock ship can rotate with the wind around the vertical line of centers of weathercock on hydrostatic by mooring, thus makes the position of minimum fore mid point form annular minimum heading line.The minimum heading line of this annular defines the border of the vertical tube shape of minimum fore mid point forbidden zone (LE district).The every root vertical line being positioned at vertical tube shape border all cuts through annular minimum heading line.Submarine structure is located in LE district.

Submarine structure can be any submarine structure, such as, be further describe following submarine structure.

The present inventor recognizes around vertical line of centers have the inaccessiable region of weathercock ship.Contriver recognizes that this understanding can be used to a kind of useful mode further; a kind of Shallow Water System can be provided simply by which; this Shallow Water System can have better protected effect to (crowd) flexible delivery unit, and this Shallow Water System is easy to be designed to tool safety margin likely simultaneously.

The submarine structure of current Shallow Water System is often arranged on the suitable segment distance place below weathercock keel, in order to avoid collision.According to the present invention, the submarine structure of Shallow Water System of the present invention does not need to be arranged on the position lower than keel level, but can be arranged on the farther place of bed off sea.Keel are backbones of ship, and keel extend along boat bottom and usually form the lowermost portion of weathercock ship.The redundant length of the flexible delivery unit between suspension and submarine structure that the redundant length of the flexible delivery unit between suspended structure and submarine structure that Shallow Water System structure of the present invention allows allows than Shallow Water System of the prior art is much longer, and significantly reduce accordingly by overflexing, contact to earth and risk that towing and/or undesirable stretching cause on sea bed flexible delivery unit damages.

Should be understood that, (crowd) annex can be applied on the bow and/or on keel.If be provided with described (crowd) annex, people need to note reserving safety margin when determining the position of submarine structure.

This Shallow Water System is particularly useful in very shallow shallow water, but it may be also favourable in not too shallow shallow water.It is in the shallow water of about 200 meters that Shallow Water System preferably can be applicable to the degree of depth, is in the shallow water of about 100 meters as preferred in the degree of depth, as being in the shallow water of 80 meters in the degree of depth.

In one embodiment, for preventing weathercock ship and submarine structure from colliding further, set submarine structure is at least about 0.5 meter to the distance on border, LE district, as at least about 1 meter, as at least about 2 meters, such as, at least about 3 meters, as at least about 4 meters, as at least about 5 meters.Fore center line due to weathercock ship top usually can be crossed minimum fore mid point and stretch out, and this safety margin is particularly conducive to the situation arranging submarine structure relative to weathercock ship higher.

In one embodiment, weathercock ship fore has the highest fore mid point.The highest fore mid point is defined as the point of fore mid point through sea level, and the position on this sea level is determined by weathercock ship fully loaded in hydrostatic.Sea level is the geodial horizon in contact hydrostatic.When weathercock ship moves with the wind around vertical line of centers, the highest fore mid point determined position in hydrostatic forms the highest heading line of annular, and the highest heading line of this annular defines the vertical tube shape border of formation the highest fore mid point forbidden zone (UE district).Submarine structure is arranged in UE district.In the present embodiment, the risk of collision between weathercock ship and submarine structure is very low, unless and the disengaging of weathercock ship, otherwise can not collide in practice.

The vertical line of centers of weathercock, also can be only called vertical line of centers, is preferably the defined vertical line of centers of nominal weathercock above.

In specific environment, weather condition makes weathercock ship usually will more stably be remained on the position of slightly departing from its nominal position.For the Shallow Water System that will use in this region, the vertical line of centers adopted can be at this determined vertical line of centers in the position of movement more slightly.But people wish that this vertical line of centers is the vertical line of centers of nominal usually.

In one embodiment, weathercock ship comprises weathercock supporting structure, such as, for the chain platform supporting construction of mooring weathercock ship.Vertical line of centers is preferably across weathercock supporting structure.Weathercock supporting structure is connected to weathercock ship by rigid construction, and this rigid construction extends one section of horizontal throw from the lowest hull mid point of weathercock ship.Axis is positioned on vertical line of centers and the circle that diameter is this horizontal throw twice defines the vertical tube shape border of desirable minimum fore mid point forbidden zone (ILE district).In the present embodiment, submarine structure is arranged in ILE district.In most of the cases, ILE district and LE district basically identical, but can not get rid of a kind of situation, mooring system does not comprise the weathercock supporting structure being connected to hull by rigid construction in this case, thus cause ILE district and LE district different in certain embodiments.In this case, people wish that submarine structure is arranged in the region that ILE district and LE district overlap.

Should be understood that, the rigid construction in above embodiment, weathercock supporting structure being connected to the hull of weathercock ship can both extend in the horizontal direction, and again vertically (normally upwards) extends from hull.The horizontal throw of lowest hull mid point is only depended in ILE district.

In one embodiment, weathercock ship comprises capstan head and for rotatably mooring is to the weathercock supporting structure of one or more fixed sturcture by capstan head, this fixed sturcture is such as sea bed.This capstan head can be the capstan head that any one uses for outside.Available capstan head and turret system are such as described in US5517937 and US6176193.

In one embodiment, capstan head comprises the swivel being connected to or comprising top side suspended structure.This swivel is well-known in the art and can is such as described in US5517937.

Unless otherwise indicated, otherwise all Distance geometry to limit be all draw according to the average water upper thread of hydrostatic.

In one embodiment, submarine structure is arranged to have the vertex determined in hydrostatic, and its setting position is less than or equal to about 40 meters, as being less than or equal to 35 meters apart from sea, as being less than or equal to 30 meters, as being less than or equal to 25 meters, as being less than or equal to 20 meters, as being less than or equal to 18 meters, as being less than or equal to 16 meters, as being less than or equal to 14 meters, as being less than or equal to 12 meters, as being less than or equal to 10 meters.The best of submarine structure vertex is arranged preferably by size and the draft decision of the depth of water, weathercock ship.

In one embodiment, submarine structure is arranged to have the vertex determined in hydrostatic, its setting position is less than or equal to about 85% of the depth of water to the distance on sea, such as be located immediately at below sea or at sea place, as being less than or equal to about 80% of the depth of water to sea distance, as being less than or equal to about 75% of the depth of water, as being less than or equal to about 60% of the depth of water, as being less than or equal to about 65% of the depth of water, as being less than or equal to about 60% of the depth of water, as being less than or equal to about 50% of the depth of water, as being less than or equal to about 25% of the depth of water.

In one embodiment, weathercock gear has lowermost portion (normally keel), the Shallow Water System arranged the vertex of submarine structure is had determine in hydrostatic to sea distance, this distance is at least shorter about 20 meters to the distance on sea than the first horizontal surface comprising weathercock ship lowermost portion determined in hydrostatic, as at least short 18 meters, as at least short 16 meters, as at least short 14 meters, or shorter.

In one embodiment, weathercock gear has the lowermost portion determined in hydrostatic, fence and hull height, the distance to sea that the Shallow Water System arranged makes the vertex of submarine structure have to determine in hydrostatic, this distance is less than or equal to about 2 times of hull height, as being less than or equal to 1.9 times of hull height, as being less than or equal to 1.8 times of hull height, as being less than or equal to 1.7 times of hull height, as being less than or equal to 1.6 times of hull height, as being less than or equal to 1.5 times of hull height, as being less than or equal to 1.4 times of hull height, as being less than or equal to 1.3 times of hull height, as being less than or equal to 1.2 times of hull height, as being less than or equal to 1.1 times of hull height, as being less than or equal to hull height, as being less than or equal to 0.9 times of hull height, as being less than or equal to 0.8 times of hull height, as being less than or equal to 0.7 times of hull height, as being less than or equal to 0.6 times of hull height, as being less than or equal to 0.5 times of hull height, as being less than or equal to 0.4 times of hull height, as being less than or equal to 0.3 times of hull height, as being less than or equal to 0.2 times of hull height, as being less than or equal to 0.1 times of hull height.

Hull height (height of hull) is defined as comprising the first horizontal surface of weathercock ship lowermost portion and comprises fence lowermost portion and and distance between the first parallel plane second plane.

In one embodiment, weathercock gear have determine in hydrostatic and average water surface curve to sea bed distance, submarine structure vertex has to sea bed distance, should add 20 meters to the weathercock ship determined in hydrostatic to sea bed distance deducting 20 meters from the large weathercock ship determined in hydrostatic to sea bed distance to sea bed distance, as added 15 meters to the large weathercock ship determined in hydrostatic to sea bed distance deducting 15 meters from the large weathercock ship determined in hydrostatic to sea bed distance, as added 10 meters to the large weathercock ship determined in hydrostatic to sea bed distance deducting 10 meters from the large weathercock ship determined in hydrostatic to sea bed distance, as added 8 meters to the large weathercock ship determined in hydrostatic to sea bed distance deducting 8 meters from the large weathercock ship determined in hydrostatic to sea bed distance.

In one embodiment, submarine structure is configured to have the vertex closer to sea, and wherein submarine structure vertex has to sea Distance geometry is enough to the distance of avoiding colliding border, weathercock Chuan LE district under usual running state.Based on the principle of the invention, those skilled in the art can design can the Shallow Water System of high security of collision free.

As further illustrated in following example, weathercock ship may stand multi-motion, these sports bags containing following be called as in the art hang down swing, pitching, rolling, surging, swaying, head shake, second order in mooring system or more order motion and/or the motion that caused by propelling, drift, drinking water, heel, trim, the motion caused by water level exchanges the motion caused by impact of (shuttle talks) with by shuttling back and forth.In this article, term " canting " includes all these motions.

In one embodiment, the weathercock ship under usual running state canting can enter immersion district, and this immersion district comprises the part in LE district.In other words, weathercock ship can enter LE district slightly due to weather conditions.The part in weathercock ship LE district that (except system damage such as mooring structure is impaired) can both enter under any state is called as LE-and immerses district.In the present embodiment, submarine structure has to sea safety distance and is enough to avoid weathercock ship in the distance immersing the border, LE district collided in district.

In one embodiment, weathercock gear has length; The submarine structure arranged has one section of horizontal throw to vertical line of centers, and this horizontal throw is less than the length of weathercock ship.

In one embodiment, submarine structure is arranged on the place having one section of horizontal throw apart from vertical line of centers, and this horizontal throw is less than about 100 meters, as being less than about 90 meters, as being less than about 80 meters, as being less than about 70 meters, as being less than about 60 meters, as being less than about 50 meters, as being less than about 40 meters, as being less than about 30 meters, as being less than about 20 meters, as being less than about 15 meters, as being less than about 10 meters.

As mentioned above, submarine structure can be any one submarine structure.In one embodiment, flexible delivery unit is connected to submarine structure.In another embodiment, flexible delivery unit can slide on submarine structure, thus the point of connection of submarine structure and flexible delivery unit can be changed.Generally, people wish that flexible delivery unit is connected to submarine structure.

In one embodiment, flexible delivery unit ends at submarine structure, and flexible delivery unit can such as be connected to rigid pipe structure, and rigid pipe structure example is as being integrally formed with submarine structure or being connected.

In one embodiment, flexible delivery unit is connected to submarine structure or passes through in the mode contacting submarine structure.In this connection, people generally wish that submarine structure has upside and supports shape, such as weep drain structure, and this weep drain structure allows flexible tube at least to go to relative to flexible delivery unit or direction from submarine structure can be moved slightly.

In one embodiment, submarine structure is fixed sturcture, is preferably directly fixed to sea bed, as riser tower and the submarine anchoring device for the one or more flexible delivery unit of anchoring.The example of this fixing submarine structure is such as recorded in US4182584 and US7040841.

In one embodiment, submarine structure is by mooring to fixed sturcture, and this submarine structure preferably comprises buoyancy system, and this submarine structure more preferably comprises Intermediate Water Depth's bow member or Intermediate Water Depth's support.This Intermediate Water Depth's bow member and Intermediate Water Depth's support are well-known in the art.

In one embodiment, submarine structure is in position by one or more flexible delivery unit.Submarine structure preferably can comprise buoyancy system, Intermediate Water Depth's bow member of submarine structure more preferably mooring.

As noted above, buoyancy system is well-known in the art, and its comprise any one in practice can to have the system that a part for flexible delivery unit to be remained on the position above sea bed by mode lower than sea water density.Buoyancy system adopts the component of one or more component comprising low density material or the air with encapsulating usually.

In one embodiment, at least one flexible delivery unit comprises buoyancy system or supports by buoyancy system, and this at least one flexible delivery unit is arranged to corrugation by this buoyancy system.This corrugation preferably comprises the waveform of flexible delivery unit, and the redundant length of the flexible delivery unit that the waveform of this flexible delivery unit is formed is greater than by submarine structure being arranged on the redundant length that may be formed below weathercock ship keel.

In one embodiment, at least one flexible delivery unit is supported to arching shape by buoyancy system.

Shallow Water System of the present invention can comprise other component; in such as prior art Shallow Water System can with the component of Shallow Water System connected applications of the present invention, this comprises such as one or more following accessory part: bending reinforced rib, exit skirt, weight coating, counterweight module, clump weight, buoyant module, fixture, bending restrictor, weep drain structure, wear protector, collision protector, fireproof protector, end fitting, steel pipe, tethers and soft lifting rope.

Accompanying drawing explanation

Below, also will more completely explain the present invention with reference to accompanying drawing in conjunction with the preferred embodiments, wherein:

Fig. 1 shows the schematic side elevation of the Shallow Water System of the present invention comprising weathercock ship, submarine structure and flexible delivery unit.

Fig. 2 shows the Shallow Water System of Fig. 1, wherein indicates another position of weathercock ship.

Fig. 3 shows the Shallow Water System of Fig. 1, wherein indicates the canting of weathercock ship.

Fig. 4 shows the Shallow Water System of Fig. 1, wherein indicates the favored area of submarine structure.

These accompanying drawings are all schematic, and simplify to know.In all of the figs, same Reference numeral is used for identical or corresponding part.

Detailed description of the invention

Further Applicable scope of the present invention is embodied from the detailed description hereafter provided.But be to be understood that, because the various changes and improvements in spirit and scope of the invention described in detail according to these are apparent to those skilled in the art, although so described detailed description and object lesson show the preferred embodiments of the present invention, only provide in an exemplary fashion.

Fig. 1 shows the diagrammatic side view of the Shallow Water System of the present invention comprising weathercock ship 3, submarine structure 1 and flexible delivery unit 2.Submarine structure 1 is fixed to sea bed 7.The lowermost portion of weathercock ship is keel 12.Perpendicular line " capstan head line of centers " is the vertical line of centers of nominal weathercock.As shown in the figure, weathercock ship can be positioned at amphi position and peri position.This will be described further in fig. 2.

Fig. 2 shows the Shallow Water System of Fig. 1, wherein indicates the dynamic rear position with the wind relative to weathercock ship 3 position drawn completely.Moving in rear position with the wind, the cue mark of weathercock ship is 11.Pointed immersion district 5 is around the hull bottom of weathercock ship and fore.Immerse the part being positioned at fore front in district 5 be enter LE district immersion part and be called as LE-and immerse district, namely weathercock ship immerses the immersion part in LE district.At the near position of weathercock ship, weathercock ship is closer to nominal weathercock perpendicular line and capstan head line of centers.In the distant positions of weathercock ship, weathercock ship is more away from the vertical line of centers of nominal weathercock and capstan head line of centers.

Sea 8 represents the preferred upper limit of submarine structure.Shown one section of safety distance of being separated by with keel 12 plane 4 represent the preferred lower limit of the vertex of submarine structure 1.Below immersion district 5 around keel and be located at the front in the immersion district 5 in fore front represent without boats and ships district 6 region that weathercock ship can not enter.Below keel 12 is so horizontal boundary without boats and ships district 6 part, and any part of aforesaid weathercock ship 3 all can not break through to the below of this boundary in the whole design and operation life period of boats and ships.This boundary determines based on shipping draft and the motion of ship for offseting towards the boats and ships in certain direction.

Fig. 3 illustrates the Shallow Water System of Fig. 1, illustrated therein is weathercock ship 3 canting.As previously mentioned, canting can comprise hang down swing, pitching, rolling, surging, swaying, head shake, Secondary movement in mooring system and/or by the motion advanced and caused by other motion.Immersion district 5 is as shown in Figure 2 defined as the space around boats and ships nominal position, and boats and ships have part at its whole service life period and immerse this space, and this immersion district determines by the theory calculate of weathercock ship canting.

Fig. 4 shows the Shallow Water System of Fig. 1, which show the favored area of submarine structure.The vertical line of centers of nominal weathercock is here 9-10.The optimum position of submarine structure vertex weathercock ship fore front without boats and ships district 6 within.

The present invention is limited by the feature of (crowd) independent claims.Preferred embodiment limits in the dependent claims.Any Reference numeral in claim is not the scope wanting to limit them.

Although more than show some preferred embodiments, it is emphasized that the present invention is not limited to these preferred embodiments, but can be embodied according to the alternate manner limited in the theme in following claims.

Claims

1. a Shallow Water System, comprise floating weathercock ship, this floating weathercock gear has top side suspended structure, submarine structure and at least one flexible delivery unit extended from this top side suspended structure to this submarine structure, this weathercock gear has fore, this fore has minimum fore mid point, this weathercock ship is become to make it can rotate around the vertical line of centers of weathercock in hydrostatic by mooring, thus make the annularly minimum heading line motion of the position of this minimum fore mid point, this annular minimum heading line defines the vertical tube shape border in LE district, minimum fore mid point forbidden zone, this submarine structure is arranged in described LE district.

2. Shallow Water System according to claim 1, is characterized in that, described submarine structure be configured to the minor increment on border, LE district be at least 0.5 meter.

3. Shallow Water System according to claim 1 and 2, it is characterized in that, the fore of this weathercock ship has the highest fore mid point, this the highest fore mid point to be defined as in hydrostatic and weathercock ship at full load fore mid point through the point of sea plane, position annularly the highest heading line motion when weathercock ship rotates around this vertical line of centers of the highest determined fore mid point, the highest heading line of this annular limits the vertical tube shape border in UE district, the highest fore mid point forbidden zone, and this submarine structure is arranged in described UE district.

4. Shallow Water System according to claim 1, it is characterized in that, described weathercock ship comprises weathercock supporting structure, this vertical line of centers is through described weathercock supporting structure, described weathercock supporting structure is connected to described weathercock ship by rigid construction, this rigid construction extends one section of horizontal throw from the minimum fore mid point of described weathercock ship, axis on this vertical line of centers and the circle that diameter is 2 times of this horizontal throw limits the vertical tube shape border in ILE district, desirable minimum fore mid point forbidden zone, described submarine structure is arranged in described ILE district.

5. Shallow Water System according to claim 1, is characterized in that, described submarine structure is configured to have the vertex determined in hydrostatic, and it is configured to be less than or equal to 40 meters to sea distance.

6. Shallow Water System according to claim 1, it is characterized in that, this submarine structure is arranged to have the vertex closer to sea, this weathercock gear has lowermost portion, this Shallow Water System be arranged to make the vertex of this submarine structure to have to determine in hydrostatic to sea distance, should to sea distance at least shorter 20 meters to the distance on sea than the first horizontal surface comprising the lowermost portion of this weathercock ship determined in hydrostatic.

7. Shallow Water System according to claim 1, it is characterized in that, this submarine structure is arranged to have the vertex closer to sea, this weathercock gear has the lowermost portion determined in hydrostatic, fence and hull height, this hull height is defined as the first horizontal surface comprising this weathercock ship lowermost portion and the distance of the lowermost portion comprising this fence also and between the second horizontal surface of this first plane-parallel, this Shallow Water System be arranged to make the vertex of this submarine structure to have to determine in hydrostatic to sea distance, this is less than or equal to 2 times of this hull height to sea distance.

8. Shallow Water System according to claim 1, it is characterized in that, this submarine structure is configured to have the vertex closer to sea, this weathercock gear have determine in hydrostatic and average water surface curve to sea bed distance, this vertex has to sea bed distance, should add 20 meters deducting 20 meters from this weathercock ship to the sea bed distance determined in hydrostatic to sea bed distance to this weathercock ship determined in hydrostatic to sea bed distance.

9. Shallow Water System according to claim 1, it is characterized in that, described submarine structure is arranged to have the vertex closer to sea, and the described vertex of wherein said submarine structure has to sea Distance geometry is enough to avoid the distance on the border, described LE district collided with the described weathercock ship under usual running state.

10. Shallow Water System according to claim 1, it is characterized in that, this weathercock ship under usual running state canting can enter the immersion district in LE district, and described submarine structure has to sea Distance geometry is enough to the distance on the border, described LE district of avoiding colliding in described immersion district with described weathercock ship.

11. Shallow Water Systems according to claim 1, is characterized in that, described weathercock gear has length, and described submarine structure is arranged on has one section of horizontal throw place apart from described vertical line of centers, and this horizontal throw is less than the length of this weathercock ship.

12. Shallow Water Systems as claimed in claim 1, comprise floating weathercock ship, this floating weathercock gear has top side suspended structure, submarine structure and flexible delivery unit that at least one extends from this top side suspended structure to this submarine structure, this weathercock ship is become it can be rotated around the vertical line of centers of weathercock in hydrostatic by mooring, described submarine structure is arranged on has one section of horizontal throw place apart from described vertical line of centers, and this horizontal throw is less than 100 meters.

13. Shallow Water Systems according to claim 1, is characterized in that, described weathercock ship comprise capstan head and for by lashing by rotatable for described capstan head mooring to the weathercock supporting structure of sea bed and/or one or more fixed sturcture.

14. Shallow Water Systems according to claim 13, is characterized in that, described capstan head comprises the swivel being connected to or comprising described top side suspended structure.

15. Shallow Water Systems according to claim 1, is characterized in that, described submarine structure is fixed sturcture.

16. Shallow Water Systems according to claim 1, is characterized in that, described submarine structure mooring is to fixed sturcture.

17. Shallow Water Systems according to claim 1, is characterized in that, described submarine structure is held in place by described one or more flexible delivery unit.

18. Shallow Water Systems according to claim 1, is characterized in that, at least one flexible delivery unit described comprises buoyancy system or supported by this buoyancy system, and at least one flexible delivery unit described in this is arranged to corrugation by this buoyancy system.

19. Shallow Water Systems according to claim 1, is characterized in that, at least one flexible delivery unit described is supported to arching by buoyancy system.

20. Shallow Water Systems according to claim 1, is characterized in that, at least one flexible delivery unit described comprises one or more flexible risers.