Winda Beacon · Library
Corrosion under insulation Insulation keeps the heat in, and it can also hold water against the steel. Step through how water gets in, where it gathers, why it stays, which temperatures matter most and how inspectors find the damage the cladding hides.
FIG. 01 · CORROSION UNDER INSULATION (CUI) WINDA BEACON · LIBRARY cladding insulation steel wall bore 12 6 o'clock A–A failed joint seal 1 WATER INrain · deluge · condensation 2 LOW POINTSit runs down and gathers 3 HELDthe insulation keeps it wet 4 HEATmetal temperature, °C 5 FOUNDscreening through insulation SOURCES rain deluge, sprinklers cooling towers condensation WAYS IN failed joint sealant damaged cladding not refitted after work underside of horizontal runs elbows vessel bases pipe supports nozzles, drain legs often at 6 o'clock SOAKS UP EASILY mineral wool fibreglass calcium silicate TAKES UP LESS foam glass perlite HSE 2011 30–120 Cao 2022* 50–175 overlap 50–120 0 50 100 150 200 * citing NACE SP0198, API RP 583 ≈0.5 mm/y at 80 °C (HSE, US data) windows as good as where you cut pulsed eddy current remaining wall, averaged guided wave losses from ~10 % of section radiography images the wall infrared wet insulation, not corrosion neutron backscatter wet insulation, ~300 m a day Water comes from rain, deluge and sprinkler systems, cooling towers or condensation. Source: Cao et al., Metals 12(4) 561 (2022) 1 WATER IN 2 LOW POINTS 3 HELD 4 HEAT 5 FOUND 6 OUTCOME
Play all 6.5 s / 80 s
Stage 1 · WATER IN
Water comes from rain, deluge and sprinkler systems, cooling towers or condensation.