Pipeline pulling is the final and one of the most responsible process operation during construction of the trunk line underwater passage using directional drilling method. The analysis of tractive forces for pipeline pulling during construction of the trunk line underwater passage using directional drilling method demonstrated that the process complications in terms of growth of the tracking forces while pulling are caused by the following reasons: the available the borehole curvilinear sections; the borehole shoulders formed when passing in the interstratified soils with different physical and mechanical properties; the obstacles in terms of the soil massifs upstream the pipeline outlet due to available mud pads formed as a result of insufficient removal of drilling cuttings or collapse of the borehole constructed in the non-cemented soils; the borehole flow area reduction as a result of squeezing the high plasticity clays into the well. Thus, the changes introduced in the borehole geometry parameters and the passage profile during drilling and the pilot bore hole enlargement are the main reason for growth of tractive forces in the course of pipeline pulling. Therefore, prior to perform the pipeline pulling process, it is important to have the instrumental procedure for the borehole condition evaluation. Today, the only instrumental procedure to control the bore hole spatial attitude and its available deviations from the design position is inclinometer surveying method The inclinometer surveying method is used both for telemetry monitoring of the drilling tool position during pilot borehole construction and for passage profile assessment after the last stage of enlargement. In the article the main conclusions and regulations obtained as a result of the process complications and emergencies analysis during construction of the trunk line underwater passages and the causes for the process complications and emergencies occurrence are considered. The method and criterion for borehole condition assessment is given according to the data of the well inclinometer surveying. The assessment of the bore hole condition according to the data of inclinometer surveying carried out after the well enlargement, allows for developing stringent requirements to contractors' operation and acceptance of their performance results, as well as for preventing process complications and emergencies in during pipeline pulling.
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