To determine the terms of safe operation of defects in pipe sections, it is necessary to calculate the number of cycles and the magnitude of pressure drops in main pipelines during operation.
Cycling calculation is carried out according to the number of starts of pumping units at the site (process switching) using data on the outlet pressure change of the pumping stations at the process site for a calendar year. The procedure for obtaining the calculated information on the cycling of loading implies the summation of the cycling at the output of all stations of the process site. The key feature of the technique is that the cycling is calculated within the process site of the main pipeline. The use of a single value of cycling for the process site in further calculations provides a margin of safe operation life of pipe section defects. With this approach, it is necessary to take into account the unique loading of each section, which is especially important for calculating the period of safe operation of defects.
The article considers the peculiarities of pressure drop consideration to calculate the cycling, and an analysis has been made of pressure drop consideration and the calculation results of cycling of loading for the existing pipeline. According to the results of the analysis, proposals were developed for improving the cycling determination algorithm, taking into account the loading with internal pressure of each section of the pipeline.
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