Parameters & Survey Techniques Used for Operating and Maintaining the Integrity of 55 Years Old High Pressure Thin Walled Seam Welded Gas Pipelines
Pipelines are considered the safest mode for oil & gas transportation. In 1950’s the pipelines were designed and constructed for a 30 years life span. However with the passage of time and as pressures were mounted on pipeline owners and operators, demanding supply of more quantities of oil & gas, even with the laying of hundreds of thousands of miles of new pipelines, dependence on old infrastructure kept on increasing thus making it essential & profitable for pipeline operators to concentrate on “maintaining the integrity” of the old pipeline asset. A new technique called Intelligent Pigging for evaluation of integrity of oil & gas pipeline integrity has been developed twenty years back. However for many pipelines this method of using intelligent pigging technology to evaluate pipeline integrity cannot be adopted due to the kind of pipeline design adopted at the time of construction of oil & gas pipelines in the 1950’s & 1960’s. For the old pipelines, hence the pipeline operators are still dependant on the older methodology of above ground surveys and evaluation methods to “ensure pipeline integrity”. Although the basic concepts for evaluating and surveying the pipeline remains the same, however use of newer technology has greatly enhanced the speed and accuracy of evaluating the buried pipeline condition viz-a-viz its integrity and hence helps in maintaining and operating the pipelines in “most efficient and safe manner”.