Laying tool for laying of submarine cables into a sea-bottom

A tool for laying submarine cables comprising a drag unit for dragging along the sea-bottom and a pulling vessel, the drag unit comprising a body and a ploughing means supported by the body for ploughing a trench in a sea or ocean bottom, a pulling tube on said drag unit for guiding submarine cables from the pulling vessel to said drag unit and down into said trench, the underside surface of the body being substantially planar and having at the rear end of the body a central notch in the central part of which said ploughing means is disposed, said ploughing means being shaped as a keel the front part of which is in the form of two ploughs, inclusive of an upper broad plough and a lower narrow plough, the lower plough being placed behind the upper plough, said body having an inner part which occupies a part of the pulling tube which opens into the ploughing means somewhat spaced from the very back of the ploughing means, the distance from the projection on the bottom plane of the point of the lower plough to a line perpendicular to the length axis of the drag unit limiting the stem against the plane bottom of the body is 5-8 times the ploughing depth.

A tool for laying submarine cables comprising a drag unit for dragging along the sea-bottom and a pulling vessel, the drag unit comprising a body and a ploughing means supported by the body for ploughing a trench in a sea or ocean bottom, a pulling tube on said drag unit for guiding submarine cables from the pulling vessel to said drag unit and down into said trench, the underside surface of the body being substantially planar and having at the rear end of the body a central notch in the central part of which said ploughing means is disposed, said ploughing means being shaped as a keel the front part of which is in the form of two ploughs, inclusive of an upper broad plough and a lower narrow plough, being placed behind the upper plough, said body having an inner part which occupies a part of the pulling tube which opens into the ploughing means somewhat spaced from the very back of the ploughing means, said body having a curved stem whose curvature radius exceeds the maximum ploughing depth of the stem in the area which extends to the plane bottom surface.

A tool for laying submarine cables comprising a drag unit for dragging along the sea-bottom and a pulling vessel, the drag unit comprising a body and a ploughing means supported by the body for ploughing a trench in a sea or ocean bottom, a pulling tube on said drag unit for guiding submarine cables from the pulling vessel to said drag unit and down into said trench, the underside surface of the body being substantially planar and having at the rear end of the body a central notch in the central part of which said ploughing means is disposed, said ploughing means being shaped as a keel the front part of which is in the form of two ploughs, inclusive of an upper broad plough and a lower narrow plough, the lower plough being placed behind the upper plough, said body having an inner part which occupies a part of the pulling tube which opens into the ploughing means somewhat spaced from the very back of the ploughing means and a projection on the bottom plane at the center of gravity of the drag unit situated within a triangle determined by the projection of the point of the lower plough and the line, perpendicular to the longitudinal axis of the drag unit, which delimits the stem from the plane bottom of the body.