Structural Design & Prototype Development On Deepwater Pipelines Position Measuring Device

This project rooted in the national "863" plan impotant special item "The Technology of The Submarine Pipeline Laying",aiming at developing the engineering prototype on deepwater pipelines positon measuring device in possession of intellectual property,which is applied in measuring relative positon of two underwater pipelines and bolt-flange connecting devices and realizing demestic technology research on the pipeline laying equipment of special purpose.This dissertation introduces the present underwater measuring technique and the research of pipelines postion measuring devices status domestic and overseas. Based on the working principles of taut-wire measuring technique, the overall scheme of the deepwater pipelines position measuring devices was offered, including the design of mechnical structures and control system and the primary studies on deepwater working technique.Mechanical structure of the pipelines position measuring device was detailed designed in this paper. For adapting deepwater complex environment, the dynamic sealing parts were replaced by the static sealing structures in the measuring device with magnetic coupling technique to reduce the hard degree of structure design. The strength calibration for the pressure components of the device was done by utilizing FEM analysis.Baesd on tension experiments, The curve equation of the measuring wire which was tauted was detailed studied with suspension cable theory. Combining the experimental data, the numerical relation of sag and tension-force of the measuring wire was dericated within the measuring range.The structure strength and sealing performances of the key components were verified by pressure experiment results. The measuring experimental platform was designed for different positions of underwater pipelines.It was proved that the engineering prototype was feasible by the measuring experiments on land and underwater.