Claims
- 1. The process of installing a marine operations structure in a pre-determined sea floor location, said structure having a central core and a support base having at least two differently sloped ice wall surfaces for achieving fracturing of ice features, and having at least two series of circumferentially arranged ballast tanks, comprising the steps of:
- positioning the structure over a selected sea floor location by the use of at least three tug boats connected to said structure by tension cables arranged radially with respect to said structure;
- flooding a first series of lower ballast tanks in a sequential ballasting operation;
- flooding a second series of ballast tanks located at a higher elevation within said structure than said first series of ballast tanks;
- maintaining radial forces along said tension cables during said flooding steps; and
- after said structure has become founded on the bottom of the sea, pumping sea water into fluid tanks some of which are located at an elevation above the water level.
- 2. The process of installing a marine operations structure according to claim 1, wherein said flooding steps for each of said first and second series of ballast tanks is carried out in a diametrically opposite sequential pattern in each of the series of tanks.
- 3. The process of installing a marine operations structure according to claim 1, wherein said positioning step is carried out by positioning the three tug boats radially at angles of about 120.degree. about the structure.
- 4. The process of installing a marine operations structure in a pre-determined sea location according to claim 1, wherein said positioning step is preceded by a towing step carried out by at least three tug boats which are connected to the structure by tension cables over a circumferential position described by an arc of at least 180.degree. about the vertical centerline of said structure.
- 5. The process of installing a marine operations structure according to claim 1, wherein the tension cables utilized in said positioning step are connected to the structure at the level of the main deck.
- 6. The process of deballasting and refloating an installed marine operations structure from a given sea floor location, said structure having a central core and a support base having at least two differently sloped ice wall surfaces for achieving fracturing of ice features, and having at least a first and a second series of circumferentially arranged ballast tanks positioned at different vertical elevations, comprising the steps of:
- dumping sea water from ballast tanks located at an elevation above the sea level;
- deballasting said first series of ballast tanks which are located at a higher level within the marine operations structure than said second set of ballast tanks;
- deballasting said second series of ballast tanks located at a lower elevation within the marine operations structure than said first series of ballast tanks; and
- prior to completion of the deballasting of said second series of ballast tanks, attaching tension cables between the marine structure and at least three tug boats.
- 7. The process of deballasting and refloating a marine operations structure according to claim 6, wherein said flooding steps for each of said first and second series of ballast tanks are carried out in a diametrically opposite sequential pattern in each of the series of tanks.
- 8. The process of deballasting and refloating a marine operations structure according to claim 6, wherein fluid jetting is applied to the bottom of said marine structure during the final stages of deballasting to loosen the structure from the sea floor.
- 9. The process of deballasting and refloating the marine operations structure according to claim 6, wherein the tension cables of said attaching step are radially positioned at angles of about 120.degree. with respect to the structure.
- 10. The process of deballasting and refloating the marine operations structure according to claim 6, wherein the tension cables of said attaching step are radially positioned in an arc of at least 180.degree. about the vertical centerline of said structure.
Parent Case Info
This application is a division of application Ser. No. 819,288, filed Jan. 16, 1986.
US Referenced Citations (4)
Divisions (1)
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Number |
Date |
Country |
Parent |
819288 |
Jan 1986 |
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