Support to locate internal local metal loss

 Pipeline Description:

6” crude oil gathering pipeline around Gainsborough, Lincolnshire, UK. The pipeline is 2.1km long and was built in 1985. 3P had done an ILI using GEO and MFL technology. The client requested the results urgently. A preliminary report on geometric and metal loss results was provided 24 hours after the conclusion of the pigging operations. The pipeline was reported to have an internal 6 o’clock metal loss issue over some sections. Typically, the features were extremely small by length and width in an otherwise unaffected wall. The depth of these pit and pinhole type features was significant in some cases. The client started a repair campaign without delay. Target of this campaign was to do local repairs on features exceeding a certain ERF value. 

Why is it challenging?

On day 3 after the ILI conclusion, the client called 3P and explained that the major reported features of internal metal loss in the first two repair locations could not be confirmed by UT inspectors on site. The locations were confirmed to be correct in relation to the dig-up sheets provided by 3P and reference to nearby installations (significant spools, bends, etc.). The client’s contractors were on site on standby and 3P’s advice was required immediately. 

Target of the inspection:

3P Services offered to deploy our HandyScan scanning device to guide the UT inspectors to the precise locations of the features at the external surface of the pipe.