More-and-more pipelines previoulsy considered to be non -piggable due to construction of operational conditions are now within the realm of inspection tools due to new developments. This paper focusses on both extremes, i.e. pipelines inspections with extreme long duration mainly due to low flow conditions, and on the other hand very-short pipeline inspections on a tank farm where no pig launching and receiving faciities are available.
The very long pipeline inspections put high demand on dependability of electronics, on the power supply and on the tool configuartion. Sinnce there is a growing number of pipelines that end up in the low-flow regime due to decay in production, this is an issue that stands in the focus of many operating companies.
The non-piggable pipelines combine issues like lack of pig receiving traps, short radius bends, pumping capability. A case study for recent inspection of 5 tank farm lines shows how issues like these can be overcome and how the operating company can obtain full-spec inspections results at a cost-effective operation.