Abstract: An apparatus for laying underground electric cables, in particular for high-voltage lines, having a vehicle towable along a trench and carrying, on a first van, a first deposition unit adapted to form a base layer of inert material for heat dissipation at the trench bottom. Mounted on the first van is a guide structure engaging the cable for laying it on the base layer previously compacted by a vibrating plate. A second van carries a second deposition unit forming a covering layer of inert material upon the previously laid-down base layer and cable.

Abstract: An apparatus for laying underground electric cables, in particular for high-voltage lines, comprises a vehicle (2) towable along a trench (3) and carrying, on a first van (4), a first deposition unit (12) adapted to form a base layer (13) of inert material for heat dissipation at the trench bottom. Mounted on the first van (4) is a guide structure (20) engaging the cable (21) for laying it on the base layer (13) previously compacted by a vibrating plate (18). A second van (5) carries a second deposition unit (30) forming a covering layer (31) of inert material upon the previously laid-down base layer (13) and cable (21).

Abstract: In mobile laying apparatus for laying an elongated element, such as a cable, in a trench, especially a trench in a sea bed, which apparatus is advanced in a predetermined direction and includes apparatus for digging the trench and ways along which the element slides as it is deposited in the trench, tension control apparatus and a method for preventing the accumulation of such element upstream of the laying apparatus as the element is laid. In the method, a tension force is applied to the element so that the tension thereon upstream of the laying apparatus is at least equal to the tension on the element downstream of the laying apparatus. The tension control apparatus includes motor driven rollers or tracks at the ways which engage the element. The torque which the driving motors apply or alternatively, the energization of the driving motors and the advance of the laying apparatus is controlled by the position of a portion of the element upstream of the laying apparatus.

Abstract: A device for limiting the bending radius of a submarine cable portion. The device is composed of a plurality of turbular elements (5) connected to one another in an articulated manner. Each element (5) is formed by a tubular cylindrical body (10) having two end flanges (12, 13) provided with circumferential through-holes (21, 31) for the passage of connecting members (4). One flange (12) has semi-spherical projecting members (28) in diametrically opposed positions with respect to each through-hole (21). The other flange (13) has complementary semi-spherical projecting members (28).