Method and apparatus for laying a submergible elongate structure

Claim 1

An apparatus for laying a submergible elongate structure upon the bed of a body of water comprising: a floating vessel having a generally planar deck; means connected to said deck for supporting a submergible elongate structure to be laid for translation along said deck; first cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure to be laid for applying an approximately constant axial tension upon the submergible elongate structure while said floating vessel is being advanced along a desired laying route including, a first approximately constant tension winch mounted upon the deck of said floating vessel; s first pair of spaced rails extending along and generally parallel to the deck of said floating vessel; a running assembly supported upon said rails; a selectively actuatable clamping assembly supported for translation along said rails by said running assembly; second cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure for applying an approximately constant axial tension upon the submergible elongate structure supported upon said floating vessel deck while said floating vessel is maintained in a generally stationary posture with respect to the desired laying route; and a unitary submergible ramp pivotally connected to the stern of said floating vessel for supporting between said floating vessel and the bed of the body of water a portion of the submergible elongate structure to be laid, said unitary submergible ramp including a plurality of pontoon members to buoyantly support said submergible elongate structure, and a plurality of selective vertically adjustable support rollers spaced along the length thereof to accommodate flexture of a submergible elongate structure during the laying operation.

Claim 2

An apparatus for laying a submergible elongate structure upon the bed of a body of water comprising: a floating vessel having a generally planar deck; means connected to said deck for supporting a submergible elongate structure to be laid for translation along said deck; first cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure to be laid for applying an approximately constant axial tension upon the submergible elongate structure while said floating vessel is being advanced along a desired laying route including, a first approximately constant tension winch mounted upon the deck of said floating vessel; s first pair of spaced rails extending along and generally parallel to the deck of said floating vessel; a running assembly supported upon said rails; a selectively actuatable clamping assembly supported for translation along said rails by said running assembly; second cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure for applying an approximately constant axial tension upon the submergible elongate structure supported upon said floating vessel deck while said floating vessel is maintained in a generally stationary posture with respect to the desired laying route; and a unitary submergible ramp pivotally connected to the stern of said floating vessel for supporting between said floating vessel and the bed of the body of water a portion of the submergible elongate structure to be laid, said unitary submergible ramp including a plurality of pontoon members to buoyantly support said submergible elongate structure, and a plurality of selective vertically adjustable support rollers spaced along the length thereof to accommodate flexture of a submergible elongate structure during the laying operation.

Claim 6

An apparatus for laying a submergible elongate structure upon the bed of a body of water comprising: a floating vessel having a generally planar deck; means connected to said deck for supporting a submergible elongate structure to be laid for translation along said deck; first cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure to be laid for applying an approximately constant axial tension upon the submergible elongate structure while said floating vessel is being advanced along a desired laying route, including a first approximately constant tension winch mounted upon the deck of said floating vessel, a first pair of spaced rails extending along and generally parallel to the deck of said floating vessel, a running assembly supported upon said rails, a selectively actuatable clamping assembly supported for translation along said rails by said carrying assembly, and a flexible cable connected between said first approximately constant tension winch and said running assembly; second cable tensioning means connected to said deck independently of said first cable tensioning means and selectively connectable to a submergible elongate structure for applying an approximately constant axial tension upon the submergible elongate structure supported upon said floating vessel deck while said floating vessel is maintained in a generally stationary posture with respect to the desired laying route, and a second approximately constant tension winch mounted upon the deck of said floating vessel, a second pair of spaced rails extending along and generally parallel to the deck of said floating vessel and in alignment with said first pair of spaced rails, a running assembly supported upon said second pair of spaced rails, a selectively actuatable clamping assembly supported for translation along said second pair of rails by said running assembly, and a flexible cable connected between said second constant tension winch and said running assembly; a unitary submergible ramp pivotally connected to the stern of said floating vessel for supporting between said floating vessel and the bed of the body of water a portion of the submergible elongate structure to be laid.

Claim 7

An apparatus for laying a submergible elongate structure upon the bed of a body of water comprising: a floating vessel having a generally planar deck; means connected to said deck for supporting a submergible elongate structure to be laid for translation along said deck; first cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure to be laid for applying an approximately constant axial tension upon the submergible elongate structure while said floating vessel is being advanced along a desired laying route, including a first approximately constant tension winch mounted upon the deck of said floating vessel, a first pair of spaced rails extending along and generally parallel to the deck of said floating vessel, a running assembly supported upon said rails, a selectively actuatable clamping assembly supported for translation along said rails by said carrying assembly, and a flexible cable connected between said first approximately constant tension winch and said running assembly; second cable tensioning means connected to said deck independently of said first cable tensioning means and selectively connectable to a submergible elongate structure for applying an approximately constant axial tension upon the submergible elongate structure supported upon said floating vessel deck while said floating vessel is maintained in a generally stationary posture with respect to the desired laying route, and a second approximately constant tension winch mounted upon the deck of said floating vessel, a second pair of spaced rails extending along and generally parallel to the deck of said floating vessel and in alignment with said first pair of spaced rails, a running assembly supported upon said second pair of spaced rails, a selectively actuatable clamping assembly supported for translation along said second pair of rails by said running assembly, and a flexible cable connected between said second constant tension winch and said running assembly; a unitary submergible ramp pivotally connected to the stern of said floating vessel for supporting between said floating vessel and the bed of the body of water a portion of the submergible elongate structure to be laid.

Claim 8

An apparatus for laying a submergible elongate structure upon the bed of a body of water comprising: a floating vessel having a generally planar deck; means connected to said deck for supporting a submergible elongate structure to be laid for translation along said deck; first cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure to be laid for applying an approximately constant axial tension upon the submergible elongate structure whIle said floating vessel is being advanced along a desired laying route, including a first approximately constant tension winch mounted upon the deck of said floating vessel, a first pair of spaced rails extending along and generally parallel to the deck of said floating vessel, a running assembly supported upon said rails, a selectively actuatable clamping assembly supported for translation along said rails by said carrying assembly, and a flexible cable connected between said first approximately constant tension winch and said running assembly; second cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure for applying an approximately constant axial tension upon the submergible elongate structure supported upon said floating vessel deck while said floating vessel is maintained in a generally stationary posture with respect to the desired laying route, and a second approximately constant tension winch mounted upon the deck of said floating vessel, a second pair of spaced rails extending along and generally parallel to the deck of said floating vessel and in alignment with said first pair of spaced rails, a running assembly supported upon said second pair of spaced rails, a selectively actuatable clamping assembly supported for translation along said second pair of rails by said running assembly, and a flexible cable connected between said second constant tension winch and said running assembly; a unitary submergible ramp pivotally connected to the stern of said floating vessel for supporting between said floating vessel and the bed of a body of water a portion of the submergible elongate structure to be laid, said unitary submergible ramp including, a first pair of generally coextensive, mutually parallel pontoons legs, wherein each of said first pair of pontoon legs is fashioned with an enlarged section at a first end thereof; transverse members extending between and interconnecting said first pair of pontoon legs at spaced intervals along the length thereof; means connected at the second end of said first pair of pontoon legs for connecting said first pair of pontoon legs to the stern of said floating vessel; a second pair of coextensive, mutually parallel pontoon legs, wherein each of said second pair of pontoon legs is fashioned with an enlarged section at a first end thereof; a plurality of normally extending columns interconnecting corresponding ones of said first and second pair of pontoon legs along the length thereof to form at spaced intervals along the length of said first and second pair of legs a generally U-shaped structure, in cross section, having the sides thereof formed by corresponding ones of said plurality of columns and the bottom thereof formed by one of said transverse member; a pair of supporting rollers having mutually inclined axes to cradle therebetween a submergible elongate means to be laid upon the water bed, said rollers being fixedly mounted upon the transverse member interconnecting said first pair of pontoons at the first end thereof; a transverse bridge member normally extending between corresponding ones of each of said columns spaced along the length of said pontoon legs and mounted for selective adjustment with respect thereto; and a pair of supporting rollers having mutually inclined axes to cradle therebetween a submergible elongate means to be laid upon the bed of a body of water, said pair of rollers being fixedly mounted upon each transverse member along the length of said first pair of pontoon legs.

Claim 9

An apparatus for laying a submergible elongate structure upon the bed of a body of water comprising: a floating vessel having a generally planar deck; means connected to said deck for supporting a submergible elongate structure to be laid for translation along said deck; first cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure to be laid for applying an approximately constant axial tension upon the submergible elongate structure whIle said floating vessel is being advanced along a desired laying route, including a first approximately constant tension winch mounted upon the deck of said floating vessel, a first pair of spaced rails extending along and generally parallel to the deck of said floating vessel, a running assembly supported upon said rails, a selectively actuatable clamping assembly supported for translation along said rails by said carrying assembly, and a flexible cable connected between said first approximately constant tension winch and said running assembly; second cable tensioning means connected to said deck and selectively connectable to a submergible elongate structure for applying an approximately constant axial tension upon the submergible elongate structure supported upon said floating vessel deck while said floating vessel is maintained in a generally stationary posture with respect to the desired laying route, and a second approximately constant tension winch mounted upon the deck of said floating vessel, a second pair of spaced rails extending along and generally parallel to the deck of said floating vessel and in alignment with said first pair of spaced rails, a running assembly supported upon said second pair of spaced rails, a selectively actuatable clamping assembly supported for translation along said second pair of rails by said running assembly, and a flexible cable connected between said second constant tension winch and said running assembly; a unitary submergible ramp pivotally connected to the stern of said floating vessel for supporting between said floating vessel and the bed of a body of water a portion of the submergible elongate structure to be laid, said unitary submergible ramp including, a first pair of generally coextensive, mutually parallel pontoons legs, wherein each of said first pair of pontoon legs is fashioned with an enlarged section at a first end thereof; transverse members extending between and interconnecting said first pair of pontoon legs at spaced intervals along the length thereof; means connected at the second end of said first pair of pontoon legs for connecting said first pair of pontoon legs to the stern of said floating vessel; a second pair of coextensive, mutually parallel pontoon legs, wherein each of said second pair of pontoon legs is fashioned with an enlarged section at a first end thereof; a plurality of normally extending columns interconnecting corresponding ones of said first and second pair of pontoon legs along the length thereof to form at spaced intervals along the length of said first and second pair of legs a generally U-shaped structure, in cross section, having the sides thereof formed by corresponding ones of said plurality of columns and the bottom thereof formed by one of said transverse member; a pair of supporting rollers having mutually inclined axes to cradle therebetween a submergible elongate means to be laid upon the water bed, said rollers being fixedly mounted upon the transverse member interconnecting said first pair of pontoons at the first end thereof; a transverse bridge member normally extending between corresponding ones of each of said columns spaced along the length of said pontoon legs and mounted for selective adjustment with respect thereto; and a pair of supporting rollers having mutually inclined axes to cradle therebetween a submergible elongate means to be laid upon the bed of a body of water, said pair of rollers being fixedly mounted upon each transverse member along the length of said first pair of pontoon legs.

Claim 10

A method for laying a submergible elongate structure upon the bed of a body of water comprising: supporting the submergible elongate structure at the surface of the body of water upon a floating vessel having a generally planar deck; advancing the floating vessel along a desired laying route; maintaining an approximately constant axial tension on the submergible elongate structure while the floating vessel is being advanced along the desired laying route by tensioning the submergible elongate structure by a cable tensioning system connected to the deck of the floating vessel and selectively connectable to the submergible elongate structure said step of maintaining axial tension on the elongate structure when the vessel is being advanced including the steps of, actuating a first selectively actuatable clamping assembly into frictional engagement with the submergible elongate structure to be laid upon the bed of a body of water at a first end of a first pair of spaced rails; paying out a flexible cable under constant tension from a first approximately constant tension which as the floating vessel proceeds along a laying route and the selectively actuatable clamping assembly travels to a second end of the first pair of spaced rails and the pipeline is payed off of the stern of the floating vessel; and resetting the selectively actuatable clamping assembly upon the submergible elongate structure at the first end of the first pair of spaced rails; maintaining an approximately constant axial tension on the submergible elongate structure when the floating vessel is in a stationary mode with respect to the intended laying route by a cable tensioning system connected to the deck of said floating vessel and selectively connectable to the submergible elongate structure; and supporting the submergible elongate structure within the body of water aft of the floating vessel by a unitary submergible ramp pivotally connected to the stern of the floating vessel, including the step of: positioning a plurality of selectively vertically adjustable support rollers at spaced locations along the unitary submergible ramp to accommodate for flexture of a submergible structure during the laying operation.

Claim 11

A method for laying a submergible elongate structure upon the bed of a body of water comprising: supporting the submergible elongate structure at the surface of the body of water upon a floating vessel having a generally planar deck; advancing the floating vessel along a desired laying route; maintaining an approximately constant axial tension on the submergible elongate structure while the floating vessel is being advanced along the desired laying route by tensioning the submergible elongate structure by a cable tensioning system connected to the deck of the floating vessel and selectively connectable to the submergible elongate structure said step of maintaining axial tension on the elongate structure when the vessel is being advanced including the steps of, actuating a first selectively actuatable clamping assembly into frictional engagement with the submergible elongate structure to be laid upon the bed of a body of water at a first end of a first pair of spaced rails; paying out a flexible cable under constant tension from a first approximately constant tension which as the floating vessel proceeds along a laying route and the selectively actuatable clamping assembly travels to a second end of the first pair of spaced rails and the pipeline is payed off of the stern of the floating vessel; and resetting the selectively actuatable clamping assembly upon the submergible elongate structure at the first end of the first pair of spaced rails; maintaining an approximately constant axial tension on the submergible elongate structure when the floating vessel is in a stationary mode with respect to the intended laying route by a cable tensioning system connected to the deck of said floating vessel and selectively connectable to the submergible elongate structure; and supporting the submergible elongate structure within the body of water aft of the floating vessel by a unitary submergible ramp pivotally connected to the stern of the floating vessel, including the step of: positioning a plurality of selectively vertically adjustable support rollers at spaced locations along the unitary submergible ramp to accommodate for flexture of a submergible structure during the laying operation.

Claim 13

A method for converting a conventional derrick-construction barge to a barge for laying a submergible elongate structure upon the bed of a body of water comprising the steps of: connecting a first cable tensioning means to deck of the barge for selective attachment to a submergible elongate structure to be laid for applying an approximately constant axial tension upon a submergible elongate structure while the barge is being advanced along a desired laying route, said step of connecting a first cable tensioning means for applying axial tension while the barge is being advanced includes the step of, providing a first approximately constant tension winch mounted upon the deck of the floating vessel; providing a first pair of spaced rails extending along and generally parallel to the deck of the floating vessel; providing a running assembly supported upon the rails; providing a selectively actuatable clamping assembly supported for translation along the rails by a running assembly; and providing a flexible cable connected between the first approximately constant tension winch and the running assembly; connecting a second cable tensioning means to the deck of the barge for selective attachment to a submergible elongate structure to be laid for applying an approximately constant axial tension upon the submergible elongate structure while the barge is maintained in a generally stationary posture with respect to the desired laying route; and providing a unitary submergible ramp pivotally connectable to the stern of the barge for supporting between the barge and the bed of the body of water a portion of the submergible elongate structure to be laid, including the step of providing a plurality of selective vertically adjustable support rollers spaced along the length of the unitary submergible ramp to accommodate flexture of the submergible elongate structure during the laying operation.

Claim 14

A method for converting a conventional derrick-construction barge to a barge for laying a submergible elongate structure upon the bed of a body of water comprising the steps of: connecting a first cable tensioning means to deck of the barge for selective attachment to a submergible elongate structure to be laid for applying an approximately constant axial tension upon a submergible elongate structure while the barge is being advanced along a desired laying route, said step of connecting a first cable tensioning means for applying axial tension while the barge is being advanced includes the step of, providing a first approximately constant tension winch mounted upon the deck of the floating vessel; providing a first pair of spaced rails extending along and generally parallel to the deck of the floating vessel; providing a running assembly supported upon the rails; providing a selectively actuatable clamping assembly supported for translation along the rails by a running assembly; and providing a flexible cable connected between the first approximately constant tension winch and the running assembly; connecting a second cable tensioning means to the deck of the barge for selective attachment to a submergible elongate structure to be laid for applying an approximately constant axial tension upon the submergible elongate structure while the barge is maintained in a generally stationary posture with respect to the desired laying route; and providing a unitary submergible ramp pivotally connectable to the stern of the barge for supporting between the barge and the bed of the body of water a portion of the submergible elongate structure to be laid, including the step of providing a plurality of selective vertically adjustable support rollers spaced along the length of the unitary submergible ramp to accommodate flexture of the submergible elongate structure during the laying operation.