ROZGONYuK V. Improvement of technical conditions survey and repair methods for natural gas main pipeline.

The dissertation is dedicated to the issues of natural gas pipelines operation reliability increasing during the repair and maintenance process by improvement of technical conditions survey and repair methods. An important task based on integrated approach to the evaluation of and extent of the defects as well as for the change of physical and mechanical properties during the long-term operation. An effective strategy of natural gas main pipelines integrity prediction was proposed, an ingenious mathematical simulation and software for optimization of the stress-strained state parameters during the gas pipeline repair process were developed, new design features and technology approach for hot-tapping during the natural gas main pipeline repair process using arc welding are due to the research work. Principal findings of the investigation was drawn on to make good use during the repair process on the main natural gas pipelines under operation such as Kyiv-Western Ukraine ( second line ) and Soyuz (moun tain section).