A pit dug to expose a buried pipeline at one spot: an ILI anomaly, a DCVG indication, a leak or a tie-in. Once the pipe is open, inspectors document coating condition, pit depths, wall thickness, soil and water chemistry and photographs before recoating. The bell hole report is where survey predictions get checked against reality.
Bell hole at the DCVG call shows the tape's disbonded for a metre with shallow pitting under it.
Sample the soil and any water trapped under the coating before anyone cleans the pipe. pH and bacteria evidence is gone once it is washed.
Also heard as
- integrity dig
- dig
Related terms
DCVG
Direct current voltage gradient survey that locates and sizes coating holidays on buried pipe.
ILI
In-line inspection: sending instrumented tools through a pipeline to measure wall loss, dents and cracks.
Cut-out
Section of pipe removed from service so corrosion damage can be examined, tested or replaced.
Holiday
Pinhole, void or bare spot in a coating that leaves the metal underneath exposed.