|Publication number||US3360810 A|
|Publication date||Jan 2, 1968|
|Filing date||May 21, 1965|
|Priority date||May 28, 1964|
|Also published as||DE1456235A1, DE1456235B2|
|Publication number||US 3360810 A, US 3360810A, US-A-3360810, US3360810 A, US3360810A|
|Inventors||Bob E Busking|
|Original Assignee||Shell Oil Co|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (8), Referenced by (48), Classifications (16)|
|External Links: USPTO, USPTO Assignment, Espacenet|
B. E. BUSKING Jan. 2, 1968 FLOATING RESERVOIR VESSEL OF THE DISPLACEMENT TYPE 3 Sheets-Sheet 1 1 Filed May 21,. 1965 FIG.
B E. BUSKING HIS AGENT Jan. 2., 1968 B. E. BUSKING 3,360,810
FLOATING RESERVOIR VESSEL OF THE DISPLACEMENT TYPE Filed May 21, 1965' 3 Sheets-Sheet 2 INVENTOR.
B. E. BUSKING BY: 44
HIS AGENT Jan. 2, 1968 FLOATING RESERVOIR VESSEL O1" 5 Sheets-Sheet 5 Filed May 21, 1965 INVENTOR:
B. E. BUSKING HIS AGENT United States Fatent Ofiice 3,360,810 Patented Jan. 2, 1968 3,360,810 FLOATING RESERVOIR VESSEL OF THE DISPLACEMENT TYPE Bob E. Busking, the Hague, Netherlands, assignor to Shell Oil Company, New York, N.Y., a corporation of Delaware Filed May 21, 1965, Ser. No. 457,605 Claims priority, application Netherlands, May 28, 1964,
645,951 3 Claims. (Cl. 98)
This invention relates to a floating reservoir vessel of. the displacement type for the storage of liquids, in particular for the storage of petroleum products, which may be produced from an oil-field situated beneath the surface of the sea.
The primary object of the invention is to provide a storage vessel which can be transported easily to its destination, anchored easily and securely, which is little susceptible to the effect of water wave motion, and which may be quickly and simply loaded or unloaded by means of ocean going tankers, or loaded from an oil-field or from a tanker.
Broadly, the invention comprises an oblong upright vessel adapted to float in a supporting liquid and provided with a main storage container having a liquid passage opening near each of its ends, a ballast chamber situated near one end of said storage container, and means for controlling the mass in said ballast chamber in accordance with the position of said container relative to the surface of said supporting liquid. The weight distribution and dimensions of the container are so selected that the vessel during normal operation floats in the supporting liquid in which the vessel floats in such a manner that the longitudinal axis of the vessel has a substantially Vertical direction.
In order to limit the influence of the waves present on the surface of the supporting liquid, the dimensions and the weight distribution of the container in an attractive embodiment of the invention are so selected that during normal operation the oblong vessel is entirely immersed in the supporting liquid in all possible filling conditions I of the vessel. Preferably, in such a case, both the oblong vessel and the ballast chamber are provided with relative thin tubes, a part of each of these tubes always protruding above the supporting liquid during normal operation.
In order to promote speedy loading and unloading at least one rotatable element is arranged on the upper side of the vessel, which element is provided with means for fastening the mooring cable of a ship. At least one of the said rotatable elements is provided with at least one conduit connected via a movable coupling to a conduit secured to the vessel and in communication with the container portion thereof.
Other objects and advantages of the invention will become apparent from the detailed description taken with reference to the accompanying drawings wherein:
FIGURE 5, and additionally schematically illustrating a tanker moored to the vessel.
Referring to FIGURE 1, a supporting liquid, which may be salt or fresh water, is shown at 1. The surface of the water is designated by the numeral 2 and the water floor is shown at 3. The oblong reservoir vessel 4 comprises a main storage container 5 provided with anchoring means in the form of chains 6 secured to the container 5, which chains are provided with bottom anchors 7.
As shown in FIGURES 2 and 3 the container 5 is provided at one end with one or more liquid passage openings 8, which establish communication between the interior of the container 5 and theliquid 1 in which the vessel 4 floats. The container 5 is provided at the other end with one or more ballast chambers 9. In order to ensure that the container 5 will float in the liquid 1 with its longitudinal axis in a substantially vertical direction, the container 5 may be provided near the passage openings 8 with one or more blacks of solid ballast 10.
The vessel 4 is towed empty, with its longitudinal axis substantially horizontal, to its destination. This is possible because the vessel 4 when empty possesses sufiicient buoyancy to remain floating on the surface of the water. During the towing of the vessel 4 the liquid passage openings 8 are closed. Once the vessel 4 has reached its destination the passage openings 8 are opened so that the water 1 may flow into the container 5. As a result of the weight distribution of the material of the vessel 4 and of the solid ballast 10, the vessel 4 now adopts a position in which the longitudinal axis of the container 5 has a vertical direction. The vessel 4 is subsequently anchored to the bottom 3 by means of the chains or cables 6 and the anchors 7.
Since the container 5 is of a long, slender and preferably cylindrical construction (the diameter is, for example, 20 m. and the length, for example, 200 m.), the vessel 4 penetrates deep into the water in which it floats. This results in the advantage that the vessel 4 will remain fairly still even in turbulent water.
The filling of the vessel 4 with the liquid which is to be stored, for example, crude oil obtained from a number of oil wells situated below the surface of the water, takes place through a filling pipe orconduit 13 (FIGURE 2). The oil passes through the conduit 13 and enters the upper portion of the container 5, which is initially entirely filled with water (FIGURE 2). As more oil is supplied the oil progressively displaces the water present in the container 5, and the water leaves the container 5 through the opening or openings 8.
In FIGURES 2 and 3, the water in the container 5 is designated by'the numeral 14 and the oil in the container 5 is designated by the numeral 15. Since the oil 15 has a lower specific gravity than the water 14 the oil 15 will remain floating on the water 14. Due to the difference 7 between the specific gravities of the oil and the Water,
FIGURE 1 is a schematic elevation of a vessel according to the invention floating in a supporting liquid showing means for mooring a tanker to the vessel for the unloading, or optionally, the loading of the vessel;
FIGURES 2 and 3 are diagrammatic longitudinal sections of a preferred embodiment of a vessel, respectively showing the main container in two different load conditions;
FIGURE 4 is a diagrammatic longitudinal elevation of a modified ballast control system for the reservoir vessel of FIGURES 2 and 3;
FIGURE 5 is a schematic elevation of a vessel according to the invention provided with a modified means for mooring a tanker to the vessel; and,
FIGURE 6 is a plan view of the modification shown in the vessel 4 will tend to move continually upwards as progressively more oil is introduced into the container 5. However, it is sometimes considered desirable for the vessel 4 to remain at the same depth in the supporting liquid. This can be achieved by pumping more ballast liquid 16 (for example, ballast water) into the ballast chambers 9 as the proportion of oil in the container 5 increases, and by pumping ballast liquid 16 out of the ballast chambers 9 as the proportion of oil in the con tainer 5 decreases (and hence the quantity of water in the container 5 increases).
The regulation of the quantity of ballast liquid 16 in the ballast chambers 9 may also be effected automatically, for example, by means of the system shown diagrammatically in FIGURE 2 which will now be described. A float 17, floating on the surface of the water 2 is connected to a recording device 19 by means of a suitable connection, for example, a hydraulic, electric or pneumatic connection, or simply by a rope 18. It is thus possible to determine the position of the vessel 4 relative to the surface of the water 2. The recording device 19 is connected, for example, electrically, pneumatically or hydraulically, to a control device 20. A supply conduit or pipe 21 for the supply of ballast liquid to the ballast chamber 9 is connected to the ballast chamber 9. A control valve 22 is ar ranged in the supply pipe 21. This control valve 22 is connected to the control device 20 in such a way that it can receive signals from the control device 20. A pump 24, provided with a suction pipe 25 and a discharge pipe 26 is arranged in a pump chamber 23 in the ballast chamber 9. The suction pipe 25 is in communication with the ballast chamber 9. A control valve 27 is arranged in the discharge pipe 26. The control valve 27 is connected to the control device 20 in such a way that it can receive signals from the control device 20.
The above-described apparatus operates as follows. It is assumed that the container is substantially filled with water 14, there being a small quantity of oil above the water 14, as shown in FIGURE 2. The container 5 is then gradually filled with oil 15 by means of the filling conduit 13 and the water 14 is gradually forced out of the container 5, viz. through the liquid passage openings 8. Since the specific gravity of the oil 15 which displaces the water 14 is lower than the specific gravity of the water 14, the entire vessel 4 will tend to move vertically upwards. This rising of the vessel 4 is immediately sensed by means of the float 17 and the recording device 19, whereupon the controldevice 20 receives a signal. The control device 20 thereupon transmits signals to the control valves 22 and 27. As a result the control valve 22 is opened to a greater extent and correspondingly the control valve 27 is closed to a greater extent. Consequently, more ballast liquid will be supplied to the ballast chambers 9 via pipe 21 that is withdrawn by the pipe 26. In other words, the quantity of ballast liquid 16 in the ballast chambers 9 in creases in sucha way that although more oil is stored in the container 5, the latter invariably retains substantially the same position relative to the surface of the water 2. This system insures that the container 5 is automatically kept at the same depth in the water 1, irrespective of the amount of oil admitted to the container 5 (compare FIGURES 2 and 3). When removing the oil 15 from the container 5 the system outlined above operates essentially in substantially reverse fashion to the manner described above.
Of course, it is to be understood that the pump 24, conduits-25 and 26 and valve 27 could be eliminated by replacing the valve 22 in conduit 21 with a reversible pump 50 as shown in FIGURE 4. In the modified control system of FIGURE 4 when the float 17 moves up or down due to movement of the reservoir vessel 4, the control dedevice 20 operates the pump '50 to either supply or withdraw liquid from the ballast chambers 9 via pipe 21.
The removal of the oil 15 from the container 5 is effected by means of a suction conduit23 (FIGURE 2) The conduits 13 and 28 are provided, if necessary, with control valves 29 and 30, respectively.
When the container 5 is entirely filled with oil it is desirable for this oil to be drawn off, for example, by a tanker. This can be effected in a very simple manner, provided the container 5 is equipped with a'device of the type which will not be described in greater detail.
Referring back to FIGURE 1, the vessel 4 includes a rotatable element 31 such as an annulus mounted on a rigid frame and provided with means for securing a mooring-cable 32 from a ship or tanker 33. The said securing means may consist, for example, of a capstan 34 arranged on the rotatable element31. When the ship or tanker 33 is secured 'to the capstan 34 by the mooringcable 32, the ship 33 can rotate around the vertical longitudinal axis of the vessel 4, to choose its own position, dependent on forces of wind and water current, in such a way that its bow is always facing the vessel 4. When the tanker 33 is moored in this way to the vessel 4 oil may be pumped from the vessel 4 to the ship 33 or viceversa. To this end a derrick 35 is used which is fixed to the rotatable element 31 of the vessel 4 so that it can rotate around the vertical longitudinal axis of the vessel 4. The derrick 35 is provided with at least one conduit (not shown) communicating with the conduit 28 by means of a rotatable or swivel coupling (not shown). The conduit situated on the derrick 35 is provided at one end with a hose 36 which may be connected to the nozzle of a conduit (not shown) situated on the tanker, which conduit communicates with the tankers tanks. The oil can now flow from the vessel 4 to the tanks of the tanker 33 through the conduit 28, the said movable coupling, the conduit situated on the derrick 35, the hose 36 and the conduit situated on the tanker 33, or vice-versa.
Instead of the apparatus described above it is possible to employthe embodiment as shown in FIGURES 5 and 6. In this embodiment the vessel 4 is provided on its upper side with a single turntable 37 supported on a fixed platform 39 by means of rollers 38 in such a way that the turntable 37 can rotate around the vertical longitudinal axis of the vessel 4. A pipe 40 is fixedly secured to the turntable 37. Moreover, a pipe or conduit 41, connected to the container 5, is also secured to the reservoir vessel 4. The conduits 40 and 41 are connected to each other by means of a movable coupling 42.
A hose 43, provided with float means 44, is secured to the free end of the pipe 40 (see FIGURE 6). A capstan 45 is fixedly secured on the turntable 37. A mooring cable 46 of a tanker 47 may be fastened to the capstan 45. The hose 43 remains floating on the surface of the water due to the float means 44. The end of the hose 43 may be coupled to a nozzle 48 of a pipe or conduit situated on a tanker 47.
When the tanker 47 is moored to the vessel 4 in the manner shown in top-plan view of FIGURE 6 the unloading or, optionally, the loading of the reservoir vessel 4 can be effected simply through the conduit 41, the movable coupling 42, the pipe 49, the hose 43 and the nozzle 48. Since the turntable 37 is rotatable relative to the longitudinal axis of the vessel 4 the tanker 47 will always have its bow facing the vessel 4.
The upper side of the described vessel may be provided, if desired, with a platform for the landing and taking-off of helicopters.
I claim as my invention:
1. A storage vessel for storing liquids while adapted to be supported in a body of water comprising:
substantially elongated main storage container means having liquid passage openings in the vicinity of its upper and lower ends when the longitudinal axis of said container means is substantially vertical with respect to said body of water;
said container means, when empty, possessing sufficient buoyancy to remain floating, with its longitudinal axis substantially horizontal, on the surface of the body of water;
a ballast chamber adapted to contain a ballast material forming a portion of said storage vessel;
conduit means communicating with the upper end of said container means for admitting liquidsinto said container means;
said container means, when filled with liquids, being adapted to assume a position in said body of water with its longitudinal axis disposed in a substantially vertical plane;
ballast material control means cooperating with said ballast chamber for controlling the amount of ballast material in said chamber;
vertical movement measuring means cooperating with said ballast material control means for measuring vertical movement of said vessel and admitting and withdrawing ballast material to and from said ballast chamber depending upon the degree of vertical movement of said container means;
a ballast chamber adapted to contain a ballast material forming a portion of said storage vessel;
conduit means communicating with the upper end of said container means for admitting liquids into said said ballast material being a liquid and said ballast macontainer means;
terial control means including second conduit means said container means, when filled with liquids, being communicating with said ballast chamber for admitadapted to assume a position in said body of water ting and removing said ballast liquid; with its longitudinal axis disposed in a substantially said vertical movement measuring means including vertical plane;
float means arranged adjacent the vessel and adapted 10 ballast material control means cooperating with said to freely float on the surface of said body of Water; ballast chamber for controlling the amount of balrecording means operatively associated with said float last material in said chamber;
means and adapted to detect, through said float vertical movement measuring means cooperating with means, a change in the vertical level of said vessel said ballast material control means for measuring relative to said body of water and to emit a signal in vertical movement of said vessel and admitting and response thereto; withdrawing ballast material to and from said ballast controller means operatively connected to both said rechamber depending upon the degree of vertical cording means and said second conduit means for movement of said container means; regulating the amount of ballast liquid in said ballast support means fixedly secured to the upper portion of chamber in response to signals received from said aid container means when said container means is recording means; disopsed with its longitudinal axis in a substantially said second conduit means including a first valve-convertical plane in said body of water;
trolled portion for admitting a ballast liquid into said support means normally extending above the sursaid ballast chamber and a second valve-controlled face of said body of water; portion for removing a ballast liquid from said balplatform means fixedly mounted on the upper portion last chamber; and of said support means; said controller means being operatively connected to an element operatively ured to the platform means both of said valve-controlled portions for opening and horizontally rotatable with respect to said vessel and closing the valves of said valve-controlled porwhen the longitudinal axis of said vessel is in a subtions in such a way that, when the vessel moves stantiahyverticalP1ahe;ahd
downwardly, the valve controlling the first valvecontrolled portion of said second conduit means is closed to a greater extent, thereby reducing the admission of ballast liquid into said ballast chamber additional conduit means operatively connected to both said container means and said rotatable element for discharging liquids from said container means.
3. A storage vessel as in claim 2 wherein said rotatable and the valve controlling the second valve-controlled element includes anchoring means for Securing a mooring portion of said second conduit means is closed to a Cable from p 50 that the P can rotate about the greater extent, thereby increasing the removal of vertical longitudinal axis of the vessel to choose its own ballast liquid from said ballast chamber, a reverse Position 50 that the bow of the p always faces the reaction occurring whenever the vessel moves upvessel.
wardly, so that irrespective of the volume of liquid 40 References Cited in said container, the vessel retains substantially the UNITED STATES PATENTS same vertical position relative to the surface of the body of Water. 2,731,168 1/1956 Watts. 2, A storage vessel for storing liquids while adapted to 3076205 2/1963 Schultz 9 8 be supported in a body of water comprising: 312O106 2/1964 Foster 98 X substantially elongated main storage container means 12/1964 V05 114 '5 having liquid passage openings in the vicinity of its 54620 6/1966 canngn 114 '5 3,191,388 6/1965 Ludwig 114.5 X upper and lower ends when the longitudinal axis of 3 256 537 6/1966 C1 k 5 X s 'd co t b t t I 1 ar l n iner means is su s antia y vertical wlh 3,273,526 9/1966 Glosten respect to said body of water;
said container means, when empty, possessing sufiicient buoyancy to remain floating, with its longitudinal axis substantially horizontal, on the surface of the body of water;
MILTON BUCHLER, Primary Examiner.
T. MAJOR, Assistant Examiner.
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|U.S. Classification||441/5, 114/256, 114/264, 441/28|
|International Classification||B63B27/34, E21B43/01, B65D88/78, B63B22/02|
|Cooperative Classification||B63B2001/044, E21B43/01, B65D88/78, B63B22/021, B63B2035/442|
|European Classification||E21B43/01, B65D88/78, B63B22/02B|