Pipe laying machines

A pipe-laying machine for laying large diameter pipe into an excavation, comprising in combination:

• two self-propelled trucks adapted to traverse along the respective opposite banks of the excavation;
• an upstanding supporting frame on each truck;
• a transverse beam extending between the frames of the respective trucks to bridge the excavation;
• means connecting the transverse beam with each of the two frames in such a manner as to permit the beam to adopt a variable inclination, at least one said connecting means permitting longitudinal sliding movement of the beam relative to the frame so that the beam can adopt a variable span, each connecting means comprising an articulation member in the form of a spherical joint consisting of a fork rotatably supported by the frame around an axis perpendicular to the base plane of the truck, said fork carrying a pivotably mounted ring capable of angular movement around an axis orthogonal to the first axis, whereby to permit the beam to assume any orientation relative to the vertical and horizontal planes, and the beam being supported by the pivotably mounted rings to be capable of rotating its own axis;
• a pipe lifting device supported by the beam;
• and
• means mounting the pipe lifting device for movement along the beam to traverse the width of the excavation which is bridged by the machine.