JPS5881886A - Offshore terminal with convertible mooring arrangement - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an offshore terminal for use in transferring fluids from the seabed to a moored vessel. More particularly, the present invention relates to an offshore terminal having a mooring arrangement that is easily convertible between soft moorings and soft moorings.

Subsea production and storage of hydrocarbons and related products, @
In shipping, it is now common to use offshore terminals to transfer hydrocarbons from the seabed to floating storage vessels or directly to sailing tankers.

A group of such offshore terminals are sometimes referred to as single anchor leg moorings (SALMs).

A typical SALMd consists of a pace structure installed on the seabed, on which standpipe elements are connected by universal joints or equivalent structures. The standpipe element can be rotated about two separate axes with respect to the pace by means of a universal joint. The standpipe element extends upwardly from the pace to a point at or near sea level. The standpipe element is normally supported in a near vertical position by an attached buoy or by a floating chamber within the standpipe element itself.

The upper end of the standpipe element contains a mooring turntable, by means of which the moored vessel can move the wind around the standpipe element in response to sea surface conditions, e.g. wind and wave action. can face the direction. The flowline extends from the seabed along the standpipe element and through a flowline swivel device located at or near the top of the standpipe element. These flow lines form conduits through which fluid flows between the seabed and the moored vessel.

Known mooring devices used to secure ships to SACMs and carry out loading or unloading operations from ships generally belong to one of the following basic types:

11E/, which are commonly referred to as "soft mooring" devices. These devices are often used wherever intermittent production or loading operations are acceptable. A typical soft mooring system ah consists of a flexible mooring line (e.g. hawser line) that attaches the ship to the SACM mooring turntable, and a flexible flow line (e.g. relatively soft hose). Through this flow line
Fluid flows between the ACM's flow line swivel device and the moored vessel.

The second type of mooring device is what is commonly referred to as a "soft mooring" device. These devices are generally used wherever floating storage equipment is to be permanently moored to a SALM. This is because such equipment can be used for continuous production, storage or storage in virtually any weather condition.
This is because it enables loading work. A typical rigid mooring system has a yoke element that securely attaches the vessel to the mooring turntable of the SALM. The rigid mooring system also includes an A-veh or hose supported by a yoke, and this A? Fluid flows through the tube or hose
M flows from the flow line swivel device to the moored vessel.

Depending on the strategy involved, rigid moorings are typically constructed and installed in stages. Under normal conditions, the pace, standpipe elements and mooring turntable are ready for installation before the yoke and related elements are completed. This is primarily due to the long assembly time required for the yoke and associated elements.

Therefore, even if the standpipe mains for pace and flow lines are installed, it can take weeks to complete and install the yoke, vessel and related elements, and months to produce hydrocarbons or We may have to delay loading. This delay leads to high costs and is critical to the overall economics of a particular operation, especially if the offshore field is at best marginal or is being developed in the planning stages.

Even after a rigid mooring system is installed and operating, there are times when the system must be unexpectedly put out of service for unpredictable periods of time. Such suspensions may be due to damage or mechanical failure to the yoke or vessel requiring dry docking for storage or other repairs.

In this event, production and loading operations for the affected SALM must be suspended until all repairs or replacements are completed. The preferred alternative is to relocate the permanently moored tanker and convert the equipment to a permanent soft mooring configuration.

Accordingly, there is a need for a hardened mooring system that is used to install a complete system from the time the pace and standpipe elements are installed and perform at least four intermittent loading operations until it is placed into service.

Additionally, there is a need for a mooring system that can continue to be used, at least intermittently, during periods when the rigid mooring system is not operating properly.

The present invention provides an offshore terminal, such as a SALM, that can operate in both soft and hard mooring configurations. The terminal pace and standpipe elements are installed and the necessary flow lines are completed at sea level. A mooring turntable is rotatably mounted on the upper end of the standpipe element.

A mooring turntable includes a device for attaching a flexible mooring line, such as a hawser, to the turntable in order to moor a ship to the turntable.

The flexible floating hose is connected at one end to the 70-line of the terminal and at the other end is adapted to be connected to the moored vessel for transferring fluid to the moored vessel.

In this configuration, the terminal operates in a soft mooring configuration.

Additionally, a pair of pillow blocks having semicircular surfaces are permanently attached to the mooring terminal as part of the integral structure of the turntable. In the soft mooring configuration, these pillow blocks preferably support a navigational beacon assembly with lights, foghorns, power and related equipment to make the terminal highly visible to nearby vessels. This navigation aid assembly is removed from the pillow block when the terminal is converted to a rigid mooring assembly.

In the rigid mooring configuration, the terminal further includes a mooring yoke to securely moor the vessel to the terminal. The yoke of the invention has at one end, the outer end, a device adapted to be attached to a ship, and at the other end, the inner end, an instant release device adapted to be releasably attached to a pillow block. It consists of a truss structure with In particular, the instant release device has a lower shaft of a U-shaft connector, such as a pitch bin, and a co-shaft connector is attached to the inner end of the yoke.

When assembled, the yoke is held on the mooring turntable and the connector is free to provide both pitching and rolling motion between the yoke and the turntable. The turntable will be turned by the yoke in response to movement by the ship.

Such rotation allows the ship to orient toward the wind around the turntable depending on the sea surface conditions. A conduit supported by the yoke is connected to the terminal's flow line for transferring fluid to the ship. If the yoke, connector or tanker must be removed for repair or maintenance, the terminal is quickly converted to a soft mooring configuration and the terminal continues to operate the transfer at least intermittently with minimal anchoring time. be able to.

The invention will be better understood by referring to the drawings. In the drawings, the same reference numerals indicate the same parts.

Referring in more detail to the drawings, FIG. 1 discloses an offshore terminal structure, such as a single anchor leg mooring (SALM) 10, illustrating the present invention.

The terminal IO consists of a pace 11 fixed to the seabed 12 with piles 18 or the like. A standpipe element 14 is connected to pace 11 via a universal joint 15. Therefore,
As is known in the art, the standpipe element 14 can be freely rotated about an axis with respect to the pace 11. As shown, standpipe element 141'! At its upper end it contains a floating chamber 16 which serves to keep the standpipe element 14 in a substantially vertical position in seawater 17. At least one flow line (e.g. flow line 18.19
) along or through the standpipe element 14;
It extends from the ocean floor 12 to the sea surface 20.

The mooring turntable 21 is equipped with a 30-type rotary bearing (
(not shown), the AZIA is permanently connected to the upper end of the standpipe element 14 by its equivalent structure.

This provides the mooring turntable 21 with the necessary weather vane function during fluid transfer operations. Turntable 21 also includes a fluid swivel device 218 (Figure 3.4).

At least one flow line (eg, flow line 18, 19) H is connected to a fluid swivel device to provide the necessary rotatable fluid passage through the turntable.

As shown in FIG. 1, the yoke 22 is a truss structure 22a.
It consists of The yoke has one inner end connected to the mooring turntable 21, and the other or outer end connected to the ship 28C.
e.g. storage tankers) [connected. Ship 28 is securely moored at terminal IO.

A conduit 24 extends along the yoke 22 and is connected at one end to a fluid swivel device 21a within the turntable 21. Conduit 24 serves to transfer fluid from flow lines 18, 19 to vessel 28. A nautical tanker then docks adjacent thereto to transfer fluids from the vessel 28.

The strategy involved in installing a rigid mooring system as described above ensures that pace 11 and standpipe elements 14, including turntable 21, are properly configured and ready for installation before yoke 22 and vessel 23 are present. This generally means that
This means that the UiC pace 11 and standpipe elements 14 will need to be installed for seven or more years before the rigid mooring system is finally completed and the actual fluid transfer operations are performed. Given today's economic conditions, such delays are extremely costly.

According to the invention, the terminal 10 is not scaled as a hard mooring device, but can also function as a soft mooring device (FIG. 2) until all components of the hard mooring device are completed; The final rigid mooring system can be easily and quickly converted to a soft mooring system whenever the need arises due to maintenance requirements or damage to the rigid mooring yoke or the moored storage vessel.

Referring to FIGS. 3-S, the turntable 21 of the present invention includes a nozzle 30 rotatably mounted to the standpipe element 14, as described above. A pair of spaced apart supports 31, 32 are permanently attached to the upper surface of the standpipe element 14 and support pillow blocks 33, 34, respectively. As best seen in FIG. 9, each pillow block has an upwardly open semicircular lower surface 35 having diametrically opposed guide elements 36 extending upwardly from each side thereof. ing.・
The lower surfaces 35 are aligned along a common longitudinal axis 35a. The yoke 22 is releasably secured to the pillow blocks 33, 34, as explained below.

As shown in FIG. 3, the housing 30 also has a hose guard work platform 38, a boat access area 39, and a hawser cage structure 40 spaced around its periphery.

As mentioned above, the pedal 1 with the turntable 21
1 and the standpipe element 14 are properly installed and the flow line 18,19 is connected to the floating hose arrangement 41 (FIG. 3) via the swivel device 21a at the upper end of the standpipe element 14. In the soft mooring configuration, one end of a flexible mooring line such as a hawser 42 is fixed to the eye plate 43 of the turntable 21 via the cage 40, and the other end is fixed to the ship 23aK. A floating hose arrangement 41 is connected to the vessel 23, thereby allowing normal fluid transfer operations. Since the turntable 21 is rotatable, the ship 23 can be oriented in the direction of the wind around the terminal 1o depending on the sea level conditions. In the case of a soft mooring configuration, the vessel 23 may be a voyaging tanker or a temporary storage vessel until a permanent storage vessel 23 and yoke 22 are ready.

Navigation aid assembly 44 while soft mooring is in place
(Figure 2.9 may be attached to pillow blocks 33, 34. Assemblies 44 are attached to trap terminals for location and safety.)
10 is preferably formed with a dome-shaped structure 44a having a battery 44b and various battery operated devices such as lights 44c1, foghorn 44d, etc.

Once the installation of the yoke 22 and permanently moored storage vessel 23 is ready, the soft mooring system is released (e.g., the hawser 42 and floating hose 41 are removed from the turntable 21) and the navigation aid assembly 44 is moved to the pillow block. 33. Remove from 34 10 Next, connect the yoke 22 to the turn 1-pull 21 and make minor modifications to the piping arrangement on the turntable.

Referring to FIGS. 6 and 7, the yoke 22 is composed of a truss structure 22m, and the truss structure 22a has a reinforcing plate support housing 50 at its inner end. The housing 50 has a recess 52, and the connector 53Fi is provided in this recess.

The connector 53 consists of a coupling housing 54 having an upper cylindrical passage 55 and a lower cylindrical passage 56.

The passages 55, 56 are at right angles to each other and the housing 54
extending over the entire length and width of. Housing 54 positions passageway 55 in line with opening 57 in housing 50 and connects passageway 55 and opening 57 to cough roll 158.
Preferably, it is mounted within recess 52 by inserting a. The pitch pin 59 is inserted into the passage 56 and the retaining plates 60 are then secured to both ends of the pitch pin. As shown in FIG. 7, the pitch pin 159 is long enough to extend beyond the end of the passageway 56 and both ends 61 of the pitch pin are exposed.

Both roll pin 158 and pitch pin 59 are free to rotate within their respective passages.

To install the Ellipse 22, lower the exposed ends 61 of the bitches onto the respective surfaces 35 of the pillow blocks 33, 34 (Figure S). The pitch pin 59 is guided by the guide element 36 into the pillow block 33.
(Fig. "%5%g") is positioned over the exposed end 61 between the guide element 36 and the retaining plate 6o and is delted through the hole 63 to attach the yoke 22 to the turntable 21.
Fasten it firmly to 5. Conduit 24 is then connected to fluid swivel device 21aK, and storage vessel 23 is secured to the outer end of yoke 22. Normal fluid transfer operations can then be performed as known by those skilled in the art.

It can be seen that when the ship 23 faces the direction of the wind depending on the sea surface condition, the turntable 21 and the yoke 22 are connected to rotate the turntable. Ship 23 to Terminal 1
The associated stick 53 mooring at zero allows for rolling and pitching movements of the ship.

If yoke 22 or ship 23 is damaged or needs to be repaired at the dock, simply turntable 21
', remove the conduit 24, remove the holder 62, and then tighten the pitch pin 59! Terminal 10 is removed by lifting and removing yoke 22 from locks 33,34.
Can be quickly converted to a terminal with soft mooring configuration. The hawser 42 and floating hose 41 are then attached and the terminal 10 is again ready for fluid transfer operations. The /r-gear 40 for the flexible hawser 42 is arranged diametrically opposite the point around the turntable 21 where the yoke extends when the yoke 22 is in the operative position (FIG. 1). It is preferable that the This allows the cage 40 to not impede the pitching movement of the yoke 22.

Since the invention is subject to many changes, modifications and changes in detail,
All subject matter □ described above and shown in the accompanying drawings is illustrative and is not to be construed in a limiting sense. Furthermore, all such equivalent modifications and variations are intended to be included within the spirit and scope of the invention as claimed.

[Brief explanation of the drawing]

FIG. 1 is an elevational view of the offshore terminal of the present invention in a rigid mooring configuration. FIG. 2 is a partially cut-away elevational view of the offshore terminal of FIG. 1 in a soft mooring configuration; FIG. 3 is a plan view of the mooring turntable of the offshore terminal of FIGS. 1 and 2. FIG. FIG. 4 is a sectional view taken along line 4-19 in FIG. FIG. S is a partially omitted partial sectional view taken along line ss in FIG. 4. 6 is an elevational view, partially omitted, of the inner end of the mooring yoke of the rigid mooring device shown in FIG. 1. FIG. Figure 5 is an elevational view of the holder used to secure the yoke to the tar/table of the offshore terminal in Figure 1. Figure 9 is an elevational view of the holder used in the soft mooring device of Figure 2. 10...Single anchor leg type mooring device or terminal; 12...Sea floor; 13...Pace; 14...
Standpipe element, 15... Universal joint, 16... Floating chamber, 1
8.1ia-..." sea line, 20... sea level, 21
...Mooring tar/table, 21a...Fluid swivel device, 22...Yoke, 23...Ship, 24...
Conduit, 30... Housing, 31.32... Stand, 3
3, '34...Pillow block, 35...Bottom surface, 36.
... Visiting elements, 38... Horse guard - workbench, 39
. . . yj=”-t getting on/off section, 40 . . . Hazard cage structure, 41 . . . Floating hose device, 42 . . .
... Eye plate, 44 ... Navigation aid assembly, 50
... Reinforcement plate support housing, 52 ... recess, 53.
... Connector, 54... Connection housing, 55... Upper cylindrical passage, 56... Lower cylindrical passage, 57.
... Opening, 58... Roll vinyl/, 59... Pitch pin, 60... Holding plate, 61... Exposed end, 62...
...Holding body.

Claims (1)

[Scope of Claims] (1) A convertible mooring turntable configured to be rotatably mounted on the upper end of an offshore structure, including a turntable/1 uzing, and a turntable/1 uzing. a pillow block device provided on the upper surface for fixing the rigid ship yoke assembly to the turntable Luno Uzi lug; and a device provided on the turntable/1 uzing for attaching the flexible ship mooring line to the turntable. and a device for connecting at least seven fluid transfer conduits to the turntable, the device being disposed within the turntable and connecting the at least seven fluid transfer conduits to the turntable; A convertible mooring turntable characterized in that the installation can be made into a soft mooring configuration by using a device. (2) The pillow block device includes a pair of supports provided on the upper surface of the turntable housing and spaced apart from each other, and a pillow block provided on each support,
12. The mooring turntable according to claim 11, wherein the pillow block has an upwardly open lower surface, and the lower surfaces are aligned along a common longitudinal axis. (31) The pillow block further includes a pair of guide elements spaced apart in the diametrical direction and extending upwardly from the lower surface (Claim 21) (4) The device for attaching a flexible mooring line to the turntable lugs is attached to a location around the turntable housing, and is adapted to receive the flexible mooring line. comprising: a cage structure having an open outer end; and an eye plate device provided within the cage structure on the turntable for attaching the flexible line to the turntable housing. A mooring turntable according to claim 11, characterized in that: An offshore terminal comprising: a standpipe element fixed to the seabed and extending between the seabed and the sea surface; rotatably provided at an upper end of the standpipe element;
a turntable housing; a pillow block device permanently mounted on the upper surface of the turntable housing; and a device provided on the turntable housing for attaching a flexible mooring line to the turntable housing; a mooring turntable, the mooring turntable comprising a device mounted on the turntable housing for connecting at least seven fluid transfer conduits to the turntable housing; at least one flow line extending to the turntable housing, the upper end of the at least one flow line being disposed in the turntable housing for connecting the at least one fluid transfer conduit. An offshore terminal connected to a device such that fluid can flow from said at least one flow line through said at least seven fluid transfer conduits. (6) An offshore structure according to claim 51, characterized in that the offshore structure includes a navigation aid assembly provided on the pillow block. (7) A mooring structure having an outer end and an inner end. a yoke structure; a device provided at the outer end of the mooring yoke structure for attaching the yoke structure to the floating vessel; a device provided at the inner end of the mooring yoke structure; The pillow block device receptacle of the turntable housing includes a device adapted to be received and the inside of the mooring yoke structure for releasably attaching the mooring yoke structure to the mooring turntable. and a device for releasably attaching the device at the end to the pillow block.
Offshore terminal described in section 5). (8) The pillow block equipment includes a pair of supports provided on the upper surface of the turntable housing and spaced apart from each other, and a pillow block provided on each support,
8. An offshore terminal according to claim 7, wherein each pillow block has an upwardly open lower surface that is aligned along a common longitudinal axis. (9) The device provided at the inner end of the mooring yoke structure includes a support housing that is attached to the inner end of the mooring yoke structure and has a recess on the lower surface, and a connector. the connector has an upper passage and a lower passage, positioned at right angles to each other, and
a connecting hole located within the recess of the supporting hole lug;
a roll pin extending through the upper passageway of the support housing and the connection housing and rotatably suspending the connection lug within the recess; and a roll pin located within the lower passageway of the connection housing. extending from opposite ends of the coupling housing to provide an exposed surface; t;
An offshore terminal according to claim 8(d), characterized in that the lower part of the exposed surface of the pitch pin is received by the lower surface of the pillow block. a. said device for releasably attaching said mooring yoke device to said pillow block has a retainer that is open downwardly located above each of the upper portions of said exposed surface of said pitch bin; Claim No.
Offshore terminal described in section 9). I. Claim fi(), characterized in that each of said pillow blocks further includes a pair of guide elements diametrically spaced apart and extending upwardly from said lower surface.
Offshore terminal described in paragraph 1. υ said device for attaching a flexible mooring line to said turntable housing, said flexible mooring line being attached to said flexible mooring line at a point about said turntable housing generally diametrically opposed to said point of extension of said yoke; a cage structure open at an outer end for receiving a line; and an eye provided within the cage structure on the turntable housing for attaching the flexible tether line to the turntable housing. An offshore terminal according to claim α1, characterized in that it comprises a plate device. a3 A quickly releasable mooring yoke structure for use in offshore terminals having a rotatable mooring turntable at the upper end, the outer end having an inner end and an outer end, the outer end being attached to a floating vessel. The connector comprises an upper lath structure adapted to be attached, a support housing attached to the inner end of the mooring yoke structure and having a recess in its lower surface, and a connector. and a connecting housing having a lower passageway positioned at right angles to each other and located within the recess of the support housing, and extending through the upper passageway of the support housing and the connecting housing such that the connecting housing is rotatable into the recess. a roll pin suspended in the lower passageway of the coupling housing and a pitch pin extending from opposite ends of the coupling housing to provide an exposed surface, the lower portion of the exposed surface of the pitch pin being suspended in the mooring yoke structure. This is a device to attach the mooring turntable to the offshore terminal's mooring turntable. Quickly releasable yaw and grip features. Structure for sound.