Marine pipeline installation system

Claim 2

A submarine pipeline installation apparatus for forming a ditch and for laying a generally rigid pipeline in the formed ditch from a surface vessel in a marine environment in a combined operation comprising: a. a supportive, rigid frame adapted to travel on the water bottom; b. ditch forming means attached to said frame on its lower side for forming the ditch for the generally rigid pipeline in the water bottom; c. a series of aligned, supportive surface means for providing substantially all the structural support to the pipeline after the pipeline leaves the surface vessel but before the pipeline enters the ditch, said supportive surface means rigidly mounted on and carried by said frame on its upper side substantially above the operative portions of said ditch forming means, each successive one of said series being lower than or substantially equal to the height of the supporting surface of the preceding one of said supportive surface means, said supportive surface means being capable of movably and supportively receiving the generally rigid pipeline thereon and placing the generally rigid pipeline down in a continuously downward manner on the water bottom in the ditch substantially behind the operative portions of said ditch forming means; and d. towing means on said frame for connecting said frame to the surface vessel laying the pipeline for towing said frame with the vessel as it moves forward, the ditch being formed by said ditch forming means as said frame is towed forward by the surface vessel and the pipeline being simultaneously laid in the ditch from said supportive surfaces behind said ditch forming means, the ditching and laying operations for the pipeline being combined into one continuous operation without the operative portions of said ditching means having to straddle the pipeline.

Claim 3

The apparatus of claim 1 wherein there is further included: sparge means attached to said frame and oriented to lie at the bottom portion of the ditch when said frame is traveling on the water bottom, the longitudinal axis of said sparge means following a path substantially coincident with the bottom centerline portion of the ditch and being substantially coincident to the final position of the pipeline to be placed in the ditch.

Claim 4

The apparatus of claim 2, wherein said sparge means is an elongated conduit through which air and water can be dispensed, said conduit being provided with a plurality of nozzles capable of dispensing said air and said water at a high rate of pressure to the area immediately ajdacent said conduit, said sparge means occupying a position substantially coincident with the final layed position of the pipeline which is to be placed in the ditch from said rollers, said sparge means lying in the ditch longitudinally between said ditching means and a point behind said ditching means which point had been traversed by said ditching means moving with said frame, said sparge means having a length such that it occupies substantially all of the ditch between said ditching means and the point of entry of the pipeline into the ditch.

Claim 5

The apparatus of claim 1, wherein said ditch forming means comprises plow means including a ditching plow.

Claim 6

The apparatus of claim 4 wherein said plow means is vertically adjustable with respect to said frame.

Claim 7

The apparatus of claim 5, wherein there is provided a plurality of adjustment stops on said plow means, and said stops register with and connect to said frame, the position of said plow being fixable at different elevations when said stops are individually registered with and connected to said frame respectively.

Claim 8

The apparatus of claim 4, wherein said plow means is pivotally adjustable about its central longitudinal axis whereby the front tip portion of said plow can be raised or lowered.

Claim 9

The apparatus of claim 7, wherein said plow means is comprised of: a. a supportive vertical column; b. a plow body affixed to said column; and c. a shear blade attached to the front portion of said plow, said shear blade being capable of initially parting the soil encountered by said plow; and said frame is provided with an opening therein, said opening receiving said column therethrough, said column making a loose fit within said opening, and there is further provided shim means placeable within said opening for adjusting the position of said plow within said opening.

Claim 10

The apparatus of claim 4, wherein there is further provided a downwardly angled tip portion on said plow.

Claim 11

The apparatus of claim 9, wherein said shear blade forms an angle of less than 45° with said frame.

Claim 12

The apparatus of claim 10, wherein said tip portion is substantially coincident with said shear blade.

Claim 13

The apparatus of claim 9, wherein said shear blade forms an angle of less than 30° with said frame.

Claim 14

The apparatus of claim 1, wherein said frame is comprised of: a. a pair of ground contacting skids; and b. an interconnective member structurally joining said skids.

Claim 15

The apparatus of claim 13, wherein said skids are pontoons, having buoyancy tanks within, and said buoyancy tanks are capable of receiving and holding pressurized gases therein.

Claim 16

The apparatus of claim 13, wherein said skids are skewed with respect to one another, the front portion of said frame having a slightly narrower width than the rear portion of said frame, whereby some sediment is urged away from the central portion of said frame when said frame travels across the water bottom.

Claim 17

The apparatus of claim 1, further comprising mold board means connected to said frame for urging sediment away from the ditch.

Claim 18

The apparatus of claim 16, wherein said mold boards are concave on the forward surface which contacts and urges the sediment during forward motion of said frame.

Claim 19

The apparatus of claim 1, wherein said supportive surface means comprise a plurality of supporting rollers, said rollers being capable of supportively receiving the pipeline thereon and being rotatable about horizontally, laterally disposed axes.

Claim 20

A submarine pipeline installation apparatus for forming a ditch in the water bottom for a pipeline in a marine environment comprising: a. a supportive frame adapted to travel on the water bottom; b. mechanical plow means with a lowermost tip portion attached to said frame on its lower side for physically and directly cutting into and removing soils from a portion of the water bottom to form a ditch for the pipeline by pushing the soil aside; and c. sparge means attached to said frame for temporarily preventing re-entry of soil into the ditch, said sparge means being oriented for being at least generally longitudinally positioned within the ditch behind said plow means and in front of the portion of the ditch in which the pipeline is to be laid, said sparge means being an elongated, single pipe-like element attached to said frame and oriented horizontally behind and at least generally in line with the lowermost tip portion of said plow means, thereby occupying a position substantially coincident with the lowermost portion of the ditch formed by said plow means, which position will eventually be occupied by the pipeline.

Claim 21

A submarine pipeline installation apparatus for forming a ditch in the water bottom for a pipeline in a marine environment comprising: a. a supportive frame adapted to travel on the water bottom; b. mechanical plow means with a lowermost tip portion attached to said frame on its lower side for physically and directly cutting into and removing soils from a portion of the water bottom to form a ditch for the pipeline by pushing the soil aside; and c. sparge means attached to said frame for temporarily preventing re-entry of soil into the ditch, said sparge means being oriented for being at least generally longitudinally positioned within the ditch behind said plow means and in front of the portion of the ditch in which the pipeline is to be laid, said sparge means being an elongated, single pipe-like element attached to said frame and oriented horizontally behind and at least generally in line with the lowermost tip portion of said plow means, thereby occupying a position substantially coincident with the lowermost portion of the ditch formed by said plow means, which position will eventually be occupied by the pipeline.

Claim 22

The apparatus of claim 19, wherein said frame is provided on its upper side with a plurality of supporting rollers, said rollers being capable of supportively receiving the pipeline thereon.

Claim 23

The apparatus of claim 19, wherein said sparge means is comprised of at least one air jet being capable of creating a suspension of air and sediment within said ditch, and wherein there is further provided air lift means attached to said frame for removing said suspended sediment from the ditch.

Claim 24

The apparatus of claim 21, wherein said air lift means is comprised of at least one conduit, one end portion of said conduit being substantially adjacent said sparge means, the other end portion of said conduit being above and laterally offset from said sparge means.

Claim 25

The apparatus of claim 19, wherein said sparge means is provided with a plurality of water dispensing nozzles and a plurality of air dispensing nozzles, said nozzles being capable of creating a suspension of sediment within the ditch, and there is further provided air lift means on said frame downstream from the beginning of said sparge means for conveying said suspension of sediment away from the ditch.

Claim 28

The method of claim 24 wherein in step "b" the apparatus is further provided with sediment upheaval and lifting means, and there is further included the following steps: g. using in step "e" said sediment upheaval means to lift up the sediment produced in the ditching operation up out of and above the ditch; and h. allowing at least some of the lifted sediment to cover up the pipeline in the ditch after said installation apparatus has passed and the pipeline has been laid in the ditch.

Claim 29

The method of claim 25 wherein said ditching means includes a plow, and wherein in step "e" there is included the step of: pulling said plow through the water bottom to form said ditch.

Claim 30

A submarine pipeline laying and burying system for forming a ditch and for laying a generally rigid pipeline from the water surface in the formed ditch in a marine environment in a combined operation comprising: a. a surface vessel from which the pipeline is to be laid; and b. a pipeline ditching apparatus located on the water bottom with the pipeline extending in a natural catenary fashion from said surface vessel to said apparatus, said apparatus including (i) a supportive, rigid frame on the water bottom adapted to travel on the water bottom; (ii) ditch forming means attached to said frame on its lower side for forming the ditch for the generally rigid pipeline in the water bottom; (iii) a series of vertically declining, aligned, supportive surface means for providing substantially all the structural support to the pipeline after the pipeline leaves the surface vessel but before the pipeline enters the ditch, said surface means being rigidly mounted on and carried by said frame on its upper side substantially above the operative portions of said ditch forming means, said supportive surface means being capable of movably and supportively receiving the generally rigid pipeline thereon and placing the generally rigid pipeline down in a continuously downward manner on the water bottom in the ditch substantially behind the operative portions of said ditch forming means, said supportive surface means providing at least substantially all the support to the pipeline as it is suspended in at least substantially natural, catenary fashion between said surface vessel and said apparatus; and (iv) towing means on said frame for connecting said frame to the surface vessel laying the pipeline for towing said frame with the vessel as it moves forward, the ditch being formed by said ditch forming means as said frame is towed forward by the surface vessel and the pipeline being simultaneously laid in the ditch from said supportive surfaces behind said ditch forming means, the ditching and laying operations for the pipeline being combined into one continuous operation without the operative portions of said ditching means having to straddle the pipeline.

Claim 31

A submarine pipeline laying and burying system for forming a ditch and for laying a generally rigid pipeline from the water surface in the formed ditch in a marine environment in a combined operation comprising: a. a surface vessel from which the pipeline is to be laid; and b. a pipeline ditching apparatus located on the water bottom with the pipeline extending in a natural catenary fashion from said surface vessel to said apparatus, said apparatus including (i) a supportive, rigid frame on the water bottom adapted to travel on the water bottom; (ii) ditch forming means attached to said frame on its lower side for forming the ditch for the generally rigid pipeline in the water bottom; (iii) a series of vertically declining, aligned, supportive surface means for providing substantially all the structural support to the pipeline after the pipeline leaves the surface vessel but before the pipeline enters the ditch, said surface means being rigidly mounted on and carried by said frame on its upper side substantially above the operative portions of said ditch forming means, said supportive surface means being capable of movably and supportively receiving the generally rigid pipeline thereon and placing the generally rigid pipeline down in a continuously downward manner on the water bottom in the ditch substantially behind the operative portions of said ditch forming means, said supportive surface means providing at least substantially all the support to the pipeline as it is suspended in at least substantially natural, catenary fashion between said surface vessel and said apparatus; and (iv) towing means on said frame for connecting said frame to the surface vessel laying the pipeline for towing said frame with the vessel as it moves forward, the ditch being formed by said ditch forming means as said frame is towed forward by the surface vessel and the pipeline being simultaneously laid in the ditch from said supportive surfaces behind said ditch forming means, the ditching and laying operations for the pipeline being combined into one continuous operation without the operative portions of said ditching means having to straddle the pipeline.