OVERVIEW: Wet and Cold Column Externals in this petrochemical plant were partially lagged. With the vessel in service, the surface temperatures were -5°C to 25°C, causing the substrate to sweat heavily during surface preparation and coating application.
The lagging was removed and Wet & Rust Tolerant Epo-chem™ RL 500PF was recommended for this application to prevent corrosion under insulation and extend the life of the shell externals.
INDUSTRY
ENVIRONMENT
Wet and Cold Column Externals
SUBSTRATE
Steel Substrate
CHALLENGE
The lagging was removed to extend the life of the shell externals. While the vessel was in service, surface preparation and corrosion application were undertaken. Surface temperatures were ranging between -5°C to around +25°C. This causes the substrate to sweat heavily during coating application.
SOLUTION
Wet & Rust Tolerant Epo-chem™ RL 500PF was recommended for this application to prevent CUI (corrosion under insulation). This system requires minimum surface preparation (i.e. no need for dry grit blasting). Rain, water, condensation or high humidity have no effect on freshly painted surfaces.
In this case, abrasive blasting was possible and coating was applied to an average DFT of 300µm total, achieved in two coats
PRODUCTS
OUTCOME
This is a prime example of innovative technology being used to save the Clients existing plant from the possibility of failure. The protective coating was able to provide a vast improvement in plant safety and also exceeded the engineer’s expectations, to the point that Chemco’s Epo-chem™ RL 500PF is now specified on all similar applications within this site.
Epo-chem™ RL 500PF is designed to provide corrosion protection for applications of up to 150°C and also is designed for application on new and aged galvanised steel, making it ideal for electricity pylons, exhaust stacks and CUI applications.
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