Submarine pipeline trencher

Claim 2

A submerged bottom engaging device for movement behind a surface vessel, said device including guide means for slidably engaging a submarine pipeline and guiding said device along said pipeline, and trench forming means carried by said guide means and projecting below the latter operable to form a trough in the bottom along which said device is being advanced, whereby said pipeline, rearward of said device, may be downwardly deflected by gravity into said trough, said guide means comprising a front to rear extending generally horizontal tube for lengthwise slidingly receiving said pipeline therethrough, said trench forming means including a pair of opposite side downwardly and outwardly inclined axle portions carried by said tube and a pair of large diameter support wheels journaled on said axle portions, the adjacent sides of the outer peripheral portions of said wheels being beveled and the lower marginal portions of the beveled sides of said wheels being disposed in closely opposing relation, whereby said lower marginal portions will coact to form a single trench in the soft bottom as said device is moved therealong.

Claim 3

The combination of claim 1 wherein said device includes opposite side front to rear extending skids spaced outwardly of said wheels and whose undersurfaces are disposed in a plane spaced above the lowest marginal portions of said wheels.

Claim 4

The combination of claim 2 wherein the front end portion of said tube includes means adapted to have a tow cable anchored thereto.

Claim 5

The combination of claim 1 wherein said trench forming means further includes bottom eroding means operable to loosen the soft bottom material disposed between said paths and vacuum means operable to draw away, by vacuuming, the loosened bottom material between said paths closely behind said wheels.

Claim 6

The combination of claim 4 wherein said eroding means includes water-jet means operable to discharge vertically spaced jets of water transversely of the central zone between said paths frOm opposite sides of said zone.

Claim 7

The combination of claim 5 wherein said eroding means further includes upstanding longitudinally extending baffle plates disposed closely adjacent and slightly outwardly of the water-jet means at opposite sides of said zone, whereby the soft bottom material disposed outwardly of said central zone will not be eroded by said water-jet means.

Claim 8

The combination of claim 6 wherein said guide means includes means operable to lengthwise slidingly engage said pipeline at a point disposed between the upper marginal portions of said baffle plates.

Claim 9

The combination of claim 7 including motor means drivingly connected to said wheels.

Claim 10

A submerged bottom engaging device for movement behind a surface vessel, said device including guide means for slidably engaging a submarine pipeline and guiding said device along said pipeline, and trench forming means carried by said guide means and projecting below the latter operable to form a trough in the bottom along which said device is being advanced, whereby said pipeline, rearward of said device, may be downwardly deflected by gravity into said trough, said trench forming means including a pair of opposite side large diameter support wheels adapted to depress the soft bottom surface over which the device is advanced along laterally spaced parallel paths, said trench forming means further including bottom eroding means operable to loosen the soft bottom material disposed between said paths and vacuum means operable to draw away, by vacuuming, the loosened bottom material between said paths closely behind said wheels, said eroding means including water-jet means operable to discharge vertically spaced jets of water transversely of the central zone between said paths from opposite sides of said zone, said eroding means further including upstanding longitudinally extending baffle plates disposed closely adjacent and slightly outwardly of the water-jet means at opposite sides of said zone, whereby the soft bottom material disposed outwardly of said central zone will not be eroded by said water-jet means, said guide means including means operable to lengthwise slidingly engage said pipeline at a point disposed between the upper marginal portions of said baffle plates, motor means drivingly connected to said wheels, said device including a transverse axle assembly, said wheels being journaled from opposite ends of the transverse axle assembly, said guide means and eroding means as well as said vacuum means being supported from the rear end of an elongated front to rear extending support whose front end is oscillatedly supported from said axle assembly.

Claim 11

A submerged bottom engaging device for movement behind a surface vessel, said device including guide means for slidably engaging a submarine pipeline and guiding said device along said pipeline, and trench forming means carried by said guide means and projecting below the latter operable to form a trough in the bottom along which said device is being advanced, whereby said pipeline, rearward of said device, may be downwardly deflected by gravity into said trough, said trench forming means including a pair of opposite side large diameter support wheels adapted to depress the soft bottom surface over which the device is advanced along laterally spaced parallel paths, said trench forming means further including bottom eroding means operable to loosen the soft bottom material disposed between said paths and vacuum means operable to draw away, by vacuuming, the loosened bottom material between said paths closely behind said wheels, said eroding means including water-jet means operable to discharge vertically spaced jets of water transversely of the central zone between said paths from opposite sides of said zone, said eroding means further including upstanding longitudinally extending baffle plates disposed closely adjacent and slightly outwardly of the water-jet means at opposite sides of said zone, whereby the soft bottom material disposed outwardly of said central zone will not be eroded by said water-jet means, said guide means including means operable to lengthwise slidingly engage said pipeline at a point disposed between the upper marginal portions of said baffle plates, motor means drivingly connected to said wheels, said device including a transverse axle assembly, said wheels being journaled from opposite ends of the transverse axle assembly, said guide means and eroding means as well as said vacuum means being supported from the rear end of an elongated front to rear extending support whose front end is oscillatedly supported from said axle assembly.

Claim 12

The combination of claim 9 wherein said device includes a second guide means for slidably and guidingly engaging said pipeline, said second guide means also defining a bottom engaging slide, a forwardly and downwardly inclined elongated support member having its rear end oscillatably supported from said axle assembly, said second guide means being oscillatably supported from the forward end of said forwardly and downwardly inclined support member.

Claim 13

A submerged bottom engaging device for movement behind a surface vessel, said device including guide means for slidably engaging a submarine pipeline and guiding said device along said pipeline, and trench forming means carried by said guide means and projecting below the latter operable to form a trough in the bottom along which said device is being advanced, whereby said pipeline, rearward of said device, may be downwardly deflected by gravity into said trough, said trench forming means including a pair of opposite side large diameter support wheels adapted to depress the soft bottom surface over which the device is advanced along laterally spaced parallel paths, said trench forming means further including bottom eroding means operable to loosen the soft bottom material disposed between said paths and vacuum means operable to draw away, by vacuuming, the loosened bottom material between said paths behInd said wheels, said eroding means including upstanding longitudinally extending baffle plates disposed closely adjacent and slightly outwardly of the water-jet means at opposite sides of said zone, whereby the soft bottom material disposed outwardly of said central zone will not be eroded by said water-jet means.

Claim 14

A submerged bottom engaging device for movement behind a surface vessel, said device including guide means for slidably engaging a submarine pipeline and guiding said device along said pipeline, and trench forming means carried by said guide means and projecting below the latter operable to form a trough in the bottom along which said device is being advanced, whereby said pipeline, rearward of said device, may be downwardly deflected by gravity into said trough, said trench forming means including a pair of opposite side large diameter support wheels adapted to depress the soft bottom surface over which the device is advanced along laterally spaced parallel paths, said trench forming means further including bottom eroding means operable to loosen the soft bottom material disposed between said paths and vacuum means operable to draw away, by vacuuming, the loosened bottom material between said paths behInd said wheels, said eroding means including upstanding longitudinally extending baffle plates disposed closely adjacent and slightly outwardly of the water-jet means at opposite sides of said zone, whereby the soft bottom material disposed outwardly of said central zone will not be eroded by said water-jet means.

Claim 15

The combination of claim 11 wherein said device includes second guide means for slidably and guidingly engaging said pipeline, said second guide means also defining a bottom engaging slide, a forward and downwardly inclined elongated support member having its rear end oscillatably supported from said axle assembly, said second guide means being oscillatably supported from the forward end of said support member.