Locating block caused by stuck PIGs in multi product pipeline using combination of radioisotope techniques.

Blockages in pipelines inhibit the normal use of the pipeline due to constricted flow of fluid through the pipeline. Locating blockages in pipelines is a challenge and there is an increasing demand for sensitive inspection methods to locate blockages in pipelines, caused either due to presence of foreign undesired material during commissioning or maintenance of the pipeline or due to accumulation of product remanent during the prolonged use of the pipelines. A block was caused in a multiproduct pipeline due to a stuck pig (pipe inspection gauge). Radiotracer techniques viz. gamma scanning and radiography were employed to pinpoint the block location.