November
2016
35
HYDROCARBON
ENGINEERING
C
orrosion under insulation (CUI) is a problem
experienced by businesses across the
downstream sector. As a severe form of
localised corrosion it can affect any metallic
pipework or storage tank – whether situated in a refinery,
process plant or fuel distribution facility. The damage it
causes to underlying structures can potentially destroy
the asset’s integrity and result in costly breaches. A 2013
report, ‘
Corrosion-Related Accidents in Petroleum
Refineries’,
describes an incident that occurred at a
refinery:
“The incident was primarily caused by a structural
failure of a 200 mm nominal bore (NB) carbon steel feed
pipe to the dehexaniser column on unit 35. The pipe was
insulated and the external surface of the pipe wall
beneath the insulation had corroded at a region where
water had been collecting. The corrosion had reduced
the pipe wall metal thickness to a level that could not
support the internal pressure of the process fluids and a
major process release occurred.”
1
Corrosion prevention and damage is a major cost
across many industries, including defence, refining,
A LOCAL,
GLOBAL PROBLEM
Jon Douglas, Frazer-Nash Consultancy, UK,
discusses how a new sensor
is helping the downstream sector to detect corrosion under insulation.
