CA1262445A - Marine vessel for lifting and supporting loads - Google Patents
Marine vessel for lifting and supporting loadsInfo
- Publication number
- CA1262445A CA1262445A CA000474706A CA474706A CA1262445A CA 1262445 A CA1262445 A CA 1262445A CA 000474706 A CA000474706 A CA 000474706A CA 474706 A CA474706 A CA 474706A CA 1262445 A CA1262445 A CA 1262445A
- Authority
- CA
- Canada
- Prior art keywords
- hollow column
- vessel
- water
- piston
- levelling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
- B66C23/18—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes
- B66C23/36—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes mounted on road or rail vehicles; Manually-movable jib-cranes for use in workshops; Floating cranes
- B66C23/52—Floating cranes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B35/00—Vessels or similar floating structures specially adapted for specific purposes and not otherwise provided for
- B63B35/44—Floating buildings, stores, drilling platforms, or workshops, e.g. carrying water-oil separating devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B39/00—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude
- B63B39/02—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude to decrease vessel movements by displacement of masses
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Ocean & Marine Engineering (AREA)
- Combustion & Propulsion (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Architecture (AREA)
- Jib Cranes (AREA)
- Other Liquid Machine Or Engine Such As Wave Power Use (AREA)
- Structure Of Emergency Protection For Nuclear Reactors (AREA)
- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
- Saccharide Compounds (AREA)
Abstract
ABSTRACT
The invention relates to a stabilizing device for a crane vessel of the semi-submersible type provided with an under-water hull, carrying a working platform supported above sea level by means of hollow columns, said platform carrying at least one crane, whereby the stabilizing device is housed in a hollow column, whereby the stabilizing device is constructed as a vertically movable stabilizing member which is moved downwardly by means of a crane when lifting a load from a transport vessel and moved upwardly when putting the load down on a platform.
The invention relates to a stabilizing device for a crane vessel of the semi-submersible type provided with an under-water hull, carrying a working platform supported above sea level by means of hollow columns, said platform carrying at least one crane, whereby the stabilizing device is housed in a hollow column, whereby the stabilizing device is constructed as a vertically movable stabilizing member which is moved downwardly by means of a crane when lifting a load from a transport vessel and moved upwardly when putting the load down on a platform.
Description
~gi '414,-~
The lnvention relates to a marine crane vessel of the semi-submersible type provided with an under-water hull, carrying a working platform supported above water level by means of hollow columns, said platform having at least one crane.
It is already known to apply lower ballast water cham-bers under the wa-~er level in every hollow column which chamber can be connected with the surrounding water, while in the hollow column above the water level water ballast chambers are applied, from which the water can be drained off through control valves.
Furthermore it is known to apply air chambers in every hollow column at the bottom and at the top of the column, wherein the lower air chambers have an open connection at the bottom with the surrounding water, whereas the upper air chambers have air valves for supplying or discharging air.
In both these systems, however, it takes a consider-able amount of time to refill the upper ballast chambers and to empty the lower ballast chambers, or for filling air bottles when applying upper and lower air chambers respectively.
The present invention provides a vessel of the semi-submersible type for use in lifting and supporting loads which would alter the trim of the vessel, the vessel being provided with an under-water hull carrying a working platform supported above water level and having at least one hollow column provided with a levelling device characterized in that: - said at least one hollow column communicates with the water body surrounding the vessel via at least one passage; - the levelling device comprises C
a levelliny member beincJ substantially vertically movab1e in said at least one holl.ow column and being formed as a water displacement means, and means for moving the levelling member in one vertical direction when taking up a load from an external platform, transport vessel or the like, respectively, and means for moving tlle levellinq member in lhe opposite vertical directlon when puttiny down a ].oad on an external platform, transport vessel or the like, whereby due to the movement of the ~ater displacement means water exits or enters the hollow column through said at least one passage r thereby altering the buoyancy of ~he vessel.
5everal embodiments according to the present invention will now he described with ~he help of the following descripti.on and the accompanying drawings, in which:
In Figure 1 a crane vessel is outlined, in which a first embodiment of a levelling or stabilizing device is arranged in a hollow column under the crane;
Figure 2 shows a modified embodiment of the levelling device as outlined in Figure l;
Figure 3 shows a second embodiment of levelling device Figure 4 shows a thi~d embodiment of levelling device;
Figure 5 shows a fourth embodiment of levelling device.
The crane vessel of Figure 1 comprises a hull 2 partly submerged below the water level and which, through hollow columns 3 (of which only one is shown), carries a working platform 4, on which a crane 5 is arranged.
The present levelling or stabilizing device is prefer-v ~
ably housed in two columns, although it would also be possible to house it in one or in four columns.
In Figure 1 the device consists of a sealed airtank 6, which can be moved vertically within the hollow column by a pressure cylinder 7. In the position shown, the airtank in the hollow column is at least for the greater part above the water level in the column 3, which is equal to water lev~l 1 since, connections 8 to the surrounding water are provided in the bottom of the hollow column. By moving the airtank 6 down, the crane vessel buoyancv is increased, which compensates for the force on the crane vessel during lifting to such an extent that the crane vessel remains horizontal within very narrow limits, On deposit-ing the load the airtank is restored to its lifted position above the water level.
Instead of the pressure cylinder 7 it is possible, in accordance with the embodiment shown in Figure 2, to move the air-tank 6 by using a pulling device 9, which is operated from the working platform 4~
The levelling device as shown in Figure 3 consists of a ballast block 11 vertically movable in the hollow column 3 by means of a lifting device 10 operable from the workiny platform 4, the specific gravity of said block being higher than that of water, During the lifting of a load by the crane, the ballast block 11 is lowered gradually but quickly to the dotted position shown in Figure 3, whereas on depositing the load the ballast block is restored to its lifted position above the water level.
C
4~5 Fuxthermore, the hollow colu~m is connected with the surrounding water through passages 12.
The levelling device shown in Figure 4 consists of a piston 13, which can be moved by a pressure cylinder 14 in the hollow column constructed as a cylinder. At the top, the cylinder is connected with the surrounding air through an airpipe 15, whereas passages 16 connect the space in the cylinder under ~he piston 13 with the surrounding water. Furthermore, the piston 13 is provided with a peripheral seal 17, and thus the air-filled cylinaer space above the piston remains separated from the water filled space under the piston 13.
The levelling device shown in Figure 5 comprises a pis-ton body 19 constructed in an extended manner, which can be moved in the hollow column 3 constructed as a cylinder by a lifting cylinder 20, wherein the opening in the bottom of the hollow column is of sufficient size as to allow the piston 19 to pass through. The top of the hollow column is also connected through an air pipe 21 with the surrounding air. The sealing of the piston body 19 with respect to the inner wall is realised with the help of any suitable sealing member 18.
The operation of the pressure cylinders 7, 14, the lifting cylinder 20, the pulling device 9, and the lifting device 10 is controlled by a computer in a known manner.
During the whole cycle of lifting, removing, and putting down a load by the crane the working platform is maintained horizontal within very narrow limits by the present, dynamically r~
~ - 4 -working stabilizing device, which can even continue to function during not too strong wave movements.
The invention can also be applied in a lifting ship that has no cranes but transfers the load to a platform by rapidly increasing the trim of the lifting ship or takes in a load by rapidly decreasing the trim. In order to establish these rapid changes in the trim, the invention can be applied in the same manner as is described above.
So far, a vertical direction has been mentioned, in order to show the simplicity of the construction. Another moving direction, for instance a horizontal one, could be thought of as well, since expelling water would be possible in any direction, not only downwardly.
Finally it is remarked that the invention naturally does not remain restricted to the above described embodiments, hut that other variants that operate according to the principle outlined above are also within the scope of the present invention.
The lnvention relates to a marine crane vessel of the semi-submersible type provided with an under-water hull, carrying a working platform supported above water level by means of hollow columns, said platform having at least one crane.
It is already known to apply lower ballast water cham-bers under the wa-~er level in every hollow column which chamber can be connected with the surrounding water, while in the hollow column above the water level water ballast chambers are applied, from which the water can be drained off through control valves.
Furthermore it is known to apply air chambers in every hollow column at the bottom and at the top of the column, wherein the lower air chambers have an open connection at the bottom with the surrounding water, whereas the upper air chambers have air valves for supplying or discharging air.
In both these systems, however, it takes a consider-able amount of time to refill the upper ballast chambers and to empty the lower ballast chambers, or for filling air bottles when applying upper and lower air chambers respectively.
The present invention provides a vessel of the semi-submersible type for use in lifting and supporting loads which would alter the trim of the vessel, the vessel being provided with an under-water hull carrying a working platform supported above water level and having at least one hollow column provided with a levelling device characterized in that: - said at least one hollow column communicates with the water body surrounding the vessel via at least one passage; - the levelling device comprises C
a levelliny member beincJ substantially vertically movab1e in said at least one holl.ow column and being formed as a water displacement means, and means for moving the levelling member in one vertical direction when taking up a load from an external platform, transport vessel or the like, respectively, and means for moving tlle levellinq member in lhe opposite vertical directlon when puttiny down a ].oad on an external platform, transport vessel or the like, whereby due to the movement of the ~ater displacement means water exits or enters the hollow column through said at least one passage r thereby altering the buoyancy of ~he vessel.
5everal embodiments according to the present invention will now he described with ~he help of the following descripti.on and the accompanying drawings, in which:
In Figure 1 a crane vessel is outlined, in which a first embodiment of a levelling or stabilizing device is arranged in a hollow column under the crane;
Figure 2 shows a modified embodiment of the levelling device as outlined in Figure l;
Figure 3 shows a second embodiment of levelling device Figure 4 shows a thi~d embodiment of levelling device;
Figure 5 shows a fourth embodiment of levelling device.
The crane vessel of Figure 1 comprises a hull 2 partly submerged below the water level and which, through hollow columns 3 (of which only one is shown), carries a working platform 4, on which a crane 5 is arranged.
The present levelling or stabilizing device is prefer-v ~
ably housed in two columns, although it would also be possible to house it in one or in four columns.
In Figure 1 the device consists of a sealed airtank 6, which can be moved vertically within the hollow column by a pressure cylinder 7. In the position shown, the airtank in the hollow column is at least for the greater part above the water level in the column 3, which is equal to water lev~l 1 since, connections 8 to the surrounding water are provided in the bottom of the hollow column. By moving the airtank 6 down, the crane vessel buoyancv is increased, which compensates for the force on the crane vessel during lifting to such an extent that the crane vessel remains horizontal within very narrow limits, On deposit-ing the load the airtank is restored to its lifted position above the water level.
Instead of the pressure cylinder 7 it is possible, in accordance with the embodiment shown in Figure 2, to move the air-tank 6 by using a pulling device 9, which is operated from the working platform 4~
The levelling device as shown in Figure 3 consists of a ballast block 11 vertically movable in the hollow column 3 by means of a lifting device 10 operable from the workiny platform 4, the specific gravity of said block being higher than that of water, During the lifting of a load by the crane, the ballast block 11 is lowered gradually but quickly to the dotted position shown in Figure 3, whereas on depositing the load the ballast block is restored to its lifted position above the water level.
C
4~5 Fuxthermore, the hollow colu~m is connected with the surrounding water through passages 12.
The levelling device shown in Figure 4 consists of a piston 13, which can be moved by a pressure cylinder 14 in the hollow column constructed as a cylinder. At the top, the cylinder is connected with the surrounding air through an airpipe 15, whereas passages 16 connect the space in the cylinder under ~he piston 13 with the surrounding water. Furthermore, the piston 13 is provided with a peripheral seal 17, and thus the air-filled cylinaer space above the piston remains separated from the water filled space under the piston 13.
The levelling device shown in Figure 5 comprises a pis-ton body 19 constructed in an extended manner, which can be moved in the hollow column 3 constructed as a cylinder by a lifting cylinder 20, wherein the opening in the bottom of the hollow column is of sufficient size as to allow the piston 19 to pass through. The top of the hollow column is also connected through an air pipe 21 with the surrounding air. The sealing of the piston body 19 with respect to the inner wall is realised with the help of any suitable sealing member 18.
The operation of the pressure cylinders 7, 14, the lifting cylinder 20, the pulling device 9, and the lifting device 10 is controlled by a computer in a known manner.
During the whole cycle of lifting, removing, and putting down a load by the crane the working platform is maintained horizontal within very narrow limits by the present, dynamically r~
~ - 4 -working stabilizing device, which can even continue to function during not too strong wave movements.
The invention can also be applied in a lifting ship that has no cranes but transfers the load to a platform by rapidly increasing the trim of the lifting ship or takes in a load by rapidly decreasing the trim. In order to establish these rapid changes in the trim, the invention can be applied in the same manner as is described above.
So far, a vertical direction has been mentioned, in order to show the simplicity of the construction. Another moving direction, for instance a horizontal one, could be thought of as well, since expelling water would be possible in any direction, not only downwardly.
Finally it is remarked that the invention naturally does not remain restricted to the above described embodiments, hut that other variants that operate according to the principle outlined above are also within the scope of the present invention.
Claims (8)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A vessel of the semi-submersible type for use in lifting and supporting loads which would alter the trim of the vessel, the vessel being provided with an under-water hull carrying a working platform supported above water level and having at least one hollow column provided with a levelling device characterized in that:
- said at least one hollow column communicates with the water body surrounding the vessel via at least one passage;
- the levelling device comprises a levelling member being substantially vertically movable in said at least one hollow column and being formed as a water displacement means, and means for moving the levelling member in one vertical direction when taking up a load from an external platform, transport vessel or the like, respectively, and means for moving the levelling member in the opposite vertical direction when putting down a load on an external platform, transport vessel or the like, whereby due to the movement of the water displacement means water exits or enters the hollow column through said at least one passage, thereby altering the buoyancy of the vessel.
- said at least one hollow column communicates with the water body surrounding the vessel via at least one passage;
- the levelling device comprises a levelling member being substantially vertically movable in said at least one hollow column and being formed as a water displacement means, and means for moving the levelling member in one vertical direction when taking up a load from an external platform, transport vessel or the like, respectively, and means for moving the levelling member in the opposite vertical direction when putting down a load on an external platform, transport vessel or the like, whereby due to the movement of the water displacement means water exits or enters the hollow column through said at least one passage, thereby altering the buoyancy of the vessel.
2. A vessel according to claim 1, characterized in that the levelling member consists of an airtank vertically movable in the hollow column, the bottom side of the hollow column being connected with the surrounding water through passages.
3. A vessel according to claim 1, characterized in that the levelling member consists of a ballast block vertically movable in the hollow column, the specific gravity of said block being higher than that of water, and the bottom side of the hollow column being connected with the surrounding water through passages.
4. A vessel according to claim 1, characterised in that the levelling member consists of a piston vertically movable in the hollow column which is constructed as a cylinder, a sealing member being provided for sealing between the piston and the inner wall of the hollow column, the space in the hollow column under the piston is connected with the surrounding water through passages, and the space in the hollow column above the piston is connected with the surrounding air through an airpipe.
5. A vessel according to claim 1, characterised in that the levelling member consists of a piston being vertically movable within the hollow column which is constructed as a cylinder, in which a sealing member is provided for sealing between the circum-ferential surface of the piston and the inner wall of the hollow column, wherein the space in the hollow column under the piston is connected with the surrounding water through a passage of which the cross section is practically equal to the cross section of the hollow column so that said piston can be extended partially beyond the end of said passage, and wherein the space in the hollow column above the piston is connected with the surrounding air through an airpipe.
6. A vessel according to any of claims 2, 4 and 5, char-acterised in that the means for moving the levelling member com-prises a pressure cylinder.
7. A vessel according to claim 2, characterised in that the means for moving the airtank comprises a pulling device operable from the working platform and applied to the bottom side of the airtank.
8. A vessel according to claim 3, characterised in that the means for moving the ballast block comprises a lifting device.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NL8400541 | 1984-02-21 | ||
| NLAANVRAGE8400541,A NL184413C (en) | 1984-02-21 | 1984-02-21 | STABILIZER. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1262445A true CA1262445A (en) | 1989-10-24 |
Family
ID=19843514
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000474706A Expired CA1262445A (en) | 1984-02-21 | 1985-02-20 | Marine vessel for lifting and supporting loads |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS60191990A (en) |
| KR (1) | KR940001621B1 (en) |
| CA (1) | CA1262445A (en) |
| FI (1) | FI84332C (en) |
| GB (1) | GB2154527B (en) |
| NL (1) | NL184413C (en) |
| NO (1) | NO163768C (en) |
| SE (1) | SE458114B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105620680A (en) * | 2016-02-26 | 2016-06-01 | 王涵 | Flush box type multi-mode stabilization device |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6676334B2 (en) * | 2002-06-10 | 2004-01-13 | Deepwater Technologies, Inc. | Work module support vessel |
| SE535055C2 (en) * | 2009-02-13 | 2012-03-27 | Gva Consultants Ab | Method of building a floating unit |
| CN103274027A (en) * | 2013-05-03 | 2013-09-04 | 黄飞灵 | Storm-resistant and anti-seasickness vessel sailing balance mechanism |
| CN112498636A (en) * | 2020-12-30 | 2021-03-16 | 杨勇 | Semi-submersible ship with new technology |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2087606A5 (en) * | 1970-05-26 | 1971-12-31 | Delaby Francois Maxime | |
| US3741145A (en) * | 1970-11-23 | 1973-06-26 | Sperry Rand Corp | Active stabilizer for marine vessels |
| US3698345A (en) * | 1970-12-28 | 1972-10-17 | Sperry Rand Corp | Active tank stabilizer for marine vessels |
| US3708991A (en) * | 1971-02-19 | 1973-01-09 | W Barkley | Submarine home |
| GB1490068A (en) * | 1974-10-28 | 1977-10-26 | Nicol C | Floating marine structures for research or exploration |
| US4014280A (en) * | 1976-01-02 | 1977-03-29 | The United States Of America As Represented By The Secretary Of The Navy | Attitude control system for seagoing vehicles |
| NL170940C (en) * | 1977-01-20 | 1983-01-17 | Varitrac Ag | STABILIZATION DEVICE FOR A CRANE WITH UNDERWATER HULLS. |
| NL7811837A (en) * | 1978-12-04 | 1980-06-06 | Varitrac Ag | STABILIZATION SYSTEM OF A CRANE TOOLS. |
-
1984
- 1984-02-21 NL NLAANVRAGE8400541,A patent/NL184413C/en not_active IP Right Cessation
-
1985
- 1985-02-20 FI FI850691A patent/FI84332C/en not_active IP Right Cessation
- 1985-02-20 GB GB08504305A patent/GB2154527B/en not_active Expired
- 1985-02-20 NO NO850664A patent/NO163768C/en not_active IP Right Cessation
- 1985-02-20 CA CA000474706A patent/CA1262445A/en not_active Expired
- 1985-02-21 JP JP60031661A patent/JPS60191990A/en active Pending
- 1985-02-21 SE SE8500843A patent/SE458114B/en not_active IP Right Cessation
- 1985-02-21 KR KR1019850001133A patent/KR940001621B1/en not_active IP Right Cessation
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105620680A (en) * | 2016-02-26 | 2016-06-01 | 王涵 | Flush box type multi-mode stabilization device |
Also Published As
| Publication number | Publication date |
|---|---|
| SE458114B (en) | 1989-02-27 |
| JPS60191990A (en) | 1985-09-30 |
| GB8504305D0 (en) | 1985-03-20 |
| GB2154527A (en) | 1985-09-11 |
| SE8500843D0 (en) | 1985-02-21 |
| FI84332B (en) | 1991-08-15 |
| NL184413B (en) | 1989-02-16 |
| FI850691L (en) | 1985-08-22 |
| SE8500843L (en) | 1985-08-22 |
| FI850691A0 (en) | 1985-02-20 |
| NL184413C (en) | 1989-07-17 |
| NL8400541A (en) | 1985-09-16 |
| NO163768B (en) | 1990-04-09 |
| NO850664L (en) | 1985-08-22 |
| KR850006360A (en) | 1985-10-05 |
| NO163768C (en) | 1990-07-18 |
| FI84332C (en) | 1991-11-25 |
| GB2154527B (en) | 1988-06-22 |
| KR940001621B1 (en) | 1994-02-28 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |