Removable mudmat and method of use on soft floor
AssigneeMcDermott Incorporated
InventorJames A. Haney
Life of this patent
Estimating the term…
Abstract
A mudmat and mudmat removal procedure used in combination with an offshore marine structure for supporting said structure on a soft, unconsolidated seafloor during installation of said structure to the seafloor.
Claims26
In combination with a jacket having one center pile sleeve and four corner pile sleeves, and in which two adjacent corner pile sleeves define one side of the jacket, two sides of the jacket having jacket legs interposed between the adjacent corner pile sleeves and the other two sides of the jacket having horizontal-diagonal members running inwardly from the corner pile sleeves toward the center of the jacket--a removable mudmat for supporting said jacket on a soft unconsolidated seafloor during installation of said jacket to the seafloor, said mudmat comprising:
- (a) a bearing plate;
- (b) framing members which are attached to and provide support for said plate;
- and
- (c) means for removably attaching the framing members to the jacket.
In combination with a jacket having one center pile sleeve and four corner pile sleeves, and in which two adjacent corner pile sleeves define one side of the jacket, two sides of the jacket having jacket legs interposed between the adjacent corner pile sleeves and the other two sides of the jacket having horizontal-diagonal members running inwardly from the corner pile sleeves toward the center of the jacket--a method of supporting said jacket on a soft, unconsolidated seafloor during installation of said jacket to the seafloor, said method comprising the steps of:
- (a) attaching at least one mudmat to said jacket prior to the installation of the jacket to the seafloor;
- (b) detaching said mudmat from the jacket after the installation of the jacket;
- (c) attaching at least one lifting cable to the mudmat;
- and
- (d) lifting the entire mudmat off the seafloor in one piece by pulling generally vertically on the lifting cable.
In combination with a jacket having one center pile sleeve and four corner pile sleeves, and in which two adjacent corner pile sleeves define one side of the jacket, two sides of the jacket having jacket legs interposed between the adjacent corner pile sleeves and the other two sides of the jacket having horizontal-diagonal members running inwardly from the corner pile sleeves toward the center of the jacket, said horizontal-diagonal members intersecting each other - a method of supporting said jacket on a soft, unconsolidated seafloor during installation of said jacket to the seafloor, said method comprising the steps of:
- (a) providing, on each side of the jacket having jacket legs interposed between the adjacent corner pile sleeves, a mudmat having two upwardly disposed extension members and attaching the upper ends of said extension members respectively to the bottom of said jacket legs;
- (b) providing, on each of the remaining two sides of the jacket, a mudmat having three extension members, attaching two of the extension members respectively to the adjacent corner pile sleeves, and attaching the third extension member to the intersection of the two horizontal-diagonal members which extend from said adjacent corner pile sleeves;
- (c) attaching lifting cables to the mudmats;
- (d) severing the extension members;
- and
- (e) lifting the mudmats off the seafloor, each in one piece, by pulling generally vertically on the lifting cables.
Dependencies are inferred from the claim text.