Three Line Shutdown Restart Technology Research And Application

Buried heated oil pipeline restart-up is a unsteady progress with interaction of hydrodynamic and thermionic effects, the temperature field is mainly influenced by pipeline flow rate and crude oil flow characteristic.Temperature field also has counteraction to the pipeline flow rate and crude oil flow characteristics which changes with time and space continuously. The operating parameters can be determined and a reasonable startup project will be worked out through numerical simulation which provides technical support of protecting the safe operation of pipeline. In this paper the followings are carried out:Used intelligent pigging to measure the temperature of SanHua pipeline for six times. Obtained real temperature drop data. Modified Sukhov Formul based on those data.Combined with boundary conditions, worked out numerical calculation model of shutdown pipeline temperature drop rule by establishing heat transfer differential equation of shutdown pipeline. Determined related parameters in heat transfer differential equation according to data of Sanhua pipeline. Obtained suitable temperature drop equation of Sanhua pipeline.Established and worked out mathematical model of restart-up of heated oil pipeline. Obtained flow rate、pressure and temperature distribution after pipeline restart-up. Combined with detection data of different seasons of Sanhua pipeline, simulated restart-up progress and obtained flow rate、pressure and temperature changes after pipeline restart-up which is supported for practical operation.Based on mathematical model of restart-up, programmed Sanhua pipeline restart-up program which has perfect function, friendly interface and simple operation.