Simulation Testing on Shut-down and Restart-up of Hot Oil Pipelines

To know well the variation law of such parameters as temperature and pressure, etc. during shut-down and restart-up of hot oil pipelines, simulation testing on shut-down and restart-up in an overhead pipeline is carried out in Daqing Testing Base. Testing results show that temperature drop rate for the hot oil pipeline in initial stage of shut-down is faster than that of the shut-down in later stage; after pipeline shuts down and restarts up for a certain time, maximum pressure will produce. After that, the pressure will be gradually decreased with the extension of restart-up period and tend to a steady state at last. After pipeline shut-down and restart-up, outlet temperature raises rapidly with the extension of restart-up time, after the pipeline is operated for some period of time, inlet temperature at pipe end goes to a steady state; although a certain fluctuation will be produced in flowrate, it will soon attain to a steady state.