Methods and apparatus for anchoring offshore pipeline

Claim 2

An offshore flowline installation assembly operable to receive pipeline means and comprising: wellhead base means; generally upright well conduit means projecting through said wellhead base means; pipeline anchor means connected with said wellhead base to form therewith a unit that can be lowered onto a seabed; said pipeline anchor means being shiftably positionable relative to said wellhead base means; and pin pile means operable to secure said pipeline anchor means to the seabed so as to isolate said pipeline anchor means from said wellhead base means in relation to forces transmitted from said pipeline means to said pipeline anchor means; said pin pile means defining generally upright pivot axis means about which said pipeline anchor means is rotatably shiftable; and said pin pile means being anchoringly engaged with said seabed and connected in generally lateral force isolating relation with said pipeline anchor means in order to substantially prevent the transmission of lateral force from said pipeline anchor means to said generally upright well conduit means.

Claim 3

An offshore flowline installation assembly according to claim 1, wherein: said pipeline anchor means comprises a socket for receiving and securing pipeline means laid away from said installation, said socket being rotatable about at least one axis; and said socket is rotatable about an upright axis located spaced from said socket.

Claim 4

An offshore flowline installation assembly according to claim 1, wherein: said pipeline anchor means includes clamp means for securing pipeline means laid toward said installation, and an inclined ramp means extending upwardly from the plane of said clamp means in a direction generally laterally relative to a pipeline lay path, so that pipeline means laid upon said ramp means tend to gravitate downwardly toward said clamp means.

Claim 5

An offshore flowline installation assembly according to claim 1, wherein: said pipeline anchor means comprises socket means adapted to receive and secure pipeline means laid away from said installation; clamp means for securing pipeline laid toward said installation; and ramp means extending upwardly from said clamp means so that pipeline means laid upon said ramp means tend to gravitate toward said clamp means; and said anchor means is rotatable about said pin pile means to selectively position one of said socket means and said clamp means for receiving said pipeline means.

Claim 6

An offshore flowing installation assembly according to claim 1, wherein: said pipeline anchor means includes pipeline securing means, and sleeve means supporting said pipeline securing means for rotation about an upright axis of said pin pile means.

Claim 7

An offshore flowline installation assembly according to claim 5, wherein: said wellhead base means includes means for preventing shifting thereof relative to the seabed; and said pipeline securing means is displaced from said axis of said pin pile means.

Claim 8

An offshore flowline installation assembly according to claim 6, wherein: said installation includes tubular means connected with said wellhead base means and operable to rotatably mount said sleeve means and telescopingly receive said pin pile means; and said shifting preventing means comprising cleats depending from said wellhead base means.

Claim 9

An offshore wellhead flowline installation comprising: generally upright well conduit means; wellhead base means through which said generally upright wellhead conduit means projects; and pipeline anchor means connected to said wellhead base means and comprising clamp means for securing pipeline means laid toward said installation, and inclined ramp means extending upwardly from said clamp means in a direction generally laterally relative to the lay path of the pipeline means, so that pipeline means laid upon said inclined ramp means tend to gravitate downwardly toward said clamp means; said inclined ramp means being disclosed generally laterally of said generally upright well conduit means and operable to receive said pipeline means with a longitudinal axis thereof being laterally displaced from said generally upright well conduit means and guide said pipeline means axis laterally toward said generally upright, well conduit means.

Claim 10

An offshore wellhead flowline installation comprising: generally upright well conduit means; wellhead base means through which said generally upright wellhead conduit means projects; and pipeline anchor means connected to said wellhead base means and comprising clamp means for securing pipeline means laid toward said installation, and inclined ramp means extending upwardly from said clamp means in a direction generally laterally relative to the lay path of the pipeline means, so that pipeline means laid upon said inclined ramp means tend to gravitate downwardly toward said clamp means; said inclined ramp means being disclosed generally laterally of said generally upright well conduit means and operable to receive said pipeline means with a longitudinal axis thereof being laterally displaced from said generally upright well conduit means and guide said pipeline means axis laterally toward said generally upright, well conduit means.

Claim 11

A flowline installation according to claim 8, wherein: said pipeline anchor means further comprises guide socket means for receiving pipeline means laid away from said installation; and said anchor means is selectively positionable to align one of said clamp means and said socket means with pipeline means.

Claim 12

A flowline installation according to claim 8 further including: a pilot tube; a pivot sleeve; said pipeline anchor means being rigidly connected to said pivot sleeve; a pin pile insertable through said pilot tube to secure said wellhead base means and said pipeline anchor means to a seabed and to isolate said wellhead base means from forces imparted to said pipeline anchor means from said pipeline means; and said pivot sleeve being rotatably mounted on said pilot tube, permitting said pipeline anchor means to be rotated relative to said wellhead base means about an upright longitudinal axis of said pin pile.

Claim 13

A submersible wellhead flowline installation comprising: a generally upright, well conduit means; wellhead base means through which said generally upright well conduit means projects; pipeline anchor means; said wellhead base means and pipeline anchor means being connected together as a unit for simultaneous lowering onto a seabed; pin pile means securing said unit to the seabed and operable to substantially isolate said pipeline anchor means from said wellhead base means in relation to forces generated in pipeline means connected with said pipeline anchor means; said pipeline anchor means being movably rotatably positionable relative to said wellhead base means about an upright axis defined by said pin pile means; and said pipeline anchor means including first socket means for receiving pipeline means laid away from said installation and second inclined ramp means for receiving pipeline means laid toward said installation said second inclined ramp means being displaced generally laterally of said generally upright well conduit means and operable to receive said pipeline means with a longitudinal axis thereof being laterally displaced from said generally upright well conduit means and guide said pipeline means axis laterally toward said generally upright, well conduit means; said pin pile means being anchoringly engaged with said seabed and connected in generally lateral force isolating relation with said pipeline anchor means in order to substantially prevent the transmission of lateral force from said pipeline anchor means to said generally upright well conduit means.

Claim 14

A submersible wellhead flowline installation comprising: a generally upright, well conduit means; wellhead base means through which said generally upright well conduit means projects; pipeline anchor means; said wellhead base means and pipeline anchor means being connected together as a unit for simultaneous lowering onto a seabed; pin pile means securing said unit to the seabed and operable to substantially isolate said pipeline anchor means from said wellhead base means in relation to forces generated in pipeline means connected with said pipeline anchor means; said pipeline anchor means being movably rotatably positionable relative to said wellhead base means about an upright axis defined by said pin pile means; and said pipeline anchor means including first socket means for receiving pipeline means laid away from said installation and second inclined ramp means for receiving pipeline means laid toward said installation said second inclined ramp means being displaced generally laterally of said generally upright well conduit means and operable to receive said pipeline means with a longitudinal axis thereof being laterally displaced from said generally upright well conduit means and guide said pipeline means axis laterally toward said generally upright, well conduit means; said pin pile means being anchoringly engaged with said seabed and connected in generally lateral force isolating relation with said pipeline anchor means in order to substantially prevent the transmission of lateral force from said pipeline anchor means to said generally upright well conduit means.

Claim 15

A submersible pipeline anchor comprising: generally upright, well conduit means; framework means; clamp means on said framework means for receiving and securing pipeline means; and inclined ramp means extending upwardly from said clamp means in a direction generally laterally of the lay path of the pipeline means, for supporting pipeline end means laid thereacross and guiding said pipeline end means as it gravitates toward said clamp means; said inclined ramp means being displaced generally laterally of said generally upright well conduit means and operable to receive said pipeline means with a longitudinal axis thereof being laterally displaced from said generally upright well conduit means and guide said pipeline means axis laterally toward said generally upright well conduit means.

Claim 16

A submersible pipeline anchor comprising: generally upright, well conduit means; framework means; clamp means on said framework means for receiving and securing pipeline means; and inclined ramp means extending upwardly from said clamp means in a direction generally laterally of the lay path of the pipeline means, for supporting pipeline end means laid thereacross and guiding said pipeline end means as it gravitates toward said clamp means; said inclined ramp means being displaced generally laterally of said generally upright well conduit means and operable to receive said pipeline means with a longitudinal axis thereof being laterally displaced from said generally upright well conduit means and guide said pipeline means axis laterally toward said generally upright well conduit means.

Claim 17

An offshore pipeline anchor comprising: frame means; means for mounting said frame means on a seabed for rotation about an upright axis; socket means mounted on said frame means for pivotal movement about a horizontal axis, said socket means being operable to receive pipeline means laid away from said anchor; and ramp means mounted on said frame means and being inclined relative to a horizontal plane, said ramp means being positionable generally laterally relative to the lay path of said pipeline means so that said pipeline means, when laid upon said ramp, gravitates downwardly therealong to a desired position.

Claim 18

An offshore pipeline anchor comprising: frame means; means for mounting said frame means on a seabed for rotation about an upright axis; socket means mounted on said frame means for pivotal movement about a horizontal axis, said socket means being operable to receive pipeline means laid away from said anchor; and ramp means mounted on said frame means and being inclined relative to a horizontal plane, said ramp means being positionable generally laterally relative to the lay path of said pipeline means so that said pipeline means, when laid upon said ramp, gravitates downwardly therealong to a desired position.

Claim 19

A pipeline anchor according to claim 13 further including: clamp means carried by said frame means; said clamp means being located at the lower end of said ramp means to clamp pipeline means received from said ramp means.

Claim 20

A pipeline anchor according to claim 13 wherein: said anchor means further includes upright sleeve means journaled on said frame means; and said mounting means comprises pin pile means extending through said sleeve means into the seabed.

Claim 21

A pipeline anchor according to claim 13 wherein: said anchor further includes wellhead base means connected with said frame means to form a unit therewith that can be lowered to the seabed; and said frame means is rotatable relative to said wellhead base means, about an upright axis.

Claim 22

An offshore flowline apparatus comprising: an assembly located on a submerged surface and including wellhead means, and pipeline anchor means; generally upright well conduit means included in said wellhead means; isolating means operable to substantially isolate said pipeline anchor means from force transmitting communication with said wellhead means; and pipeline means connected with said pipeline anchor means; said isolating means being operable to substantially isolate said wellhead means from forces generated between said pipeline means and said pipeline anchor means during said connecting, and forces acting on said pipeline means and transmitted to said pipeline anchor means subsequent to said connecting; said isolating means comprising means being anchoringly engaged with a seabed and connected in generally lateral force isolating relation with said pipeline anchor means in order to substantially prevent the transmission of lateral force from said pipeline anchor means to said generally upright, well conduit means.

Claim 23

An offshore flowline apparatus comprising: an assembly located on a submerged surface and including wellhead means, and pipeline anchor means; generally upright well conduit means included in said wellhead means; isolating means operable to substantially isolate said pipeline anchor means from force transmitting communication with said wellhead means; and pipeline means connected with said pipeline anchor means; said isolating means being operable to substantially isolate said wellhead means from forces generated between said pipeline means and said pipeline anchor means during said connecting, and forces acting on said pipeline means and transmitted to said pipeline anchor means subsequent to said connecting; said isolating means comprising means being anchoringly engaged with a seabed and connected in generally lateral force isolating relation with said pipeline anchor means in order to substantially prevent the transmission of lateral force from said pipeline anchor means to said generally upright, well conduit means.