OVERVIEW: Steel multi-stage pump assemblies in an 80°C corrosive aqueous ammonia environment required long term protection.
The external coating system was required to act as a corrosion barrier for the pump case should any leaks occur whilst in service.
INDUSTRY
ENVIRONMENT
80°C corrosive aqueous ammonia
SUBSTRATE
Steel multi-stage pump casing, galvanised coupling
CHALLENGE
The client required an external coating system to provide long term protection to their newly purchased multi-stage pump assemblies against an aqueous ammonia environment at elevated temperatures. The coating system was required to act as a corrosion barrier for the pump case should any leaks occur whilst in service. Abrasive blasting could not be deployed due to the risk of damaging critical components.
SOLUTION
We recommended RL 500PF which primes and finishes in 1 coat. This coating system requires minimal surface preparation. It is moisture/surface tolerant coating is ideal for site maintenance contracts. Rain or high humidity has no effect on painted surfaces.
We followed this with RW 500, a solvent-free epoxy Novolac which imparts outstanding protection to metal substrates. It forms a durable barrier resistant to abrasion, erosion, thermal shock, and the most aggressive environments of high temperature and chemicals in immersed and non-immersed conditions.
SCOPE
Mask off seal areas, ID plates and critical exposed fittings
Mechanically prep surface
Solvent wash with MEK
Prime with 1 coat RL 500PF to prepared surfaces
Apply 2 coats RW 500 to a DFT of 400µm
DFT checks, mount onto base frame, assemble coupling guard
PRODUCTS
Epo-chem™ RW 500 – Solvent Free Novolac Epoxy,
OUTCOME
The two product systems applied by skilled applicators resolved the no abrasive blasting issue and currently provides durable protection against a high temperature corrosive aggressive environment
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