Study of a synchronous control system for deepwater pipeline axial force and alignment Tool

Deepwater pipeline axial force and alignment Tool (AFAT) is a kind of tools used for tie-ins of deepwater pipelines, development of the AFAT will greatly improve our country´s tie-ins technological level in deep water. Adjusting devices are its key parts, they can complete the adjustment of relative position for underwater new and old pipelines in certain range to meet flange connection tools´ (FCT) requirement. In this paper, the mechanical structure and hydraulic control system based on electrohydraulic proportional directional valve of the adjusting device are designed, synchronization control scheme of “equality mode” is determined, each mathematical model of the synchronization system is built and simulation is carried which results verify synchronization control scheme´s rationality and provide theoretical basis for the establishment of hydraulic system experimental platform.