Abstract: Improved apparatus is provided for forming or erecting concrete loaded supporting means for supporting undersea pipelines at all depths and in the presence of undulating sea beds characterized by providing suspendable service module or frame means provided with pumpable concrete carrying means, vertical articulated positioning arm means mounted at one end to one end of the service module means with the one end thereof having means for releasably engaging concrete receiving pipe support module means, means for actuating the articulated positioning arm to place the support module beneath the undersea pipe to be supported, means operatively associated with the vertical articulated positioning arm and the concrete carrying means for transferring cement from the concrete carrying means to the support module.

Abstract: An apparatus for digging a trench beneath a pipeline laid on the bottom of sea or a water body, in which a clamp arrangement is split into a wider sector portion and a narrower sector portion which, as they are united under the control of a driving mechanism, embrace the pipeline and allow a set of digging discs to excavate the ground beneath the pipeline. Provisions are made to remove the debris on completion of digging. The apparatus is driven along the pipeline and means are provided to maintain both the correct vertical trim of the entire apparatus and the correct position of the pipeline track.