PIPELINE INTEGRITY MAINTENANCE USING A TETHERED INSPECTION VEHICLE (TIV)

In recent years there has been a growing awareness of the benefits of using ''intelligent pigs '' as a means of maintaining the integrity of pipelines. These pigs are autonomous devices which are transported internally through a pipeline and conduct inspections on-line without the need for taking the pipeline out of operation. This awareness has resulted in the worldwide acceptance of the use of high-resolution on-line inspection equipment for the inspection of high-pressure transmission pipelines. This inspection technology has now been further developed by British Gas for low-pressure pipelines, such as gas and water distribution pipelines, refinery pipelines and even pipelines from the jetty loading point to the terminal. Indeed, discrete sections of decommissioned high-pressure transmission pipelines can also be inspected by this method. This paper describes the tethered inspection vehicle (TIV) as a method of ensuring pipeline integrity, while eliminating unnecessary hydrostatic testing, thereby avoiding the environmental consequences of pipeline failure.