HRCSA requires a clean, tightly adhered, salt-free substrate for it's application.

This photo is of an application where the surface was contaminated and wet at time of application.

HRCSA was applied onto a cold, damp environment on an LNG pipe inside a humid LNG hut where humidity hovers around ~ 95%.

After pressure washing, substrate was blown dried with dry, clean, compressed air, wiped with TRT01 solvent soaked rag, blown dry and immediately coated with HRCSA before condensatio could form.  The rend result is rather impressive. Only minor bleed through occured.

HRCSA displaces moisture, scavenges oxygen, neutralizes acids on the steel substrate.

This application was very well performed with one minor exception:  The insides of the connections had not been blown dried before applying HRCSA penetrant under pressure inside the connection. 

The end result is that during curing, the moisture that remained had been pushed out by the chemistry resulting in the stains we see above.

The solution is simple:  Wipe the stained areas with a TRT01 solvent soaked rag to remove the stains.  In any areas where a corrosion hotspot persists, buff off the existing coating and apply a fresh coat onto the solvent activated buffed area.

HRCSA is a chemically active coating with needs adequate amount of chemistry (thickness) in order to chemically neutralize the steel substrate.

In this case, close inspection clearly reviews that the amount is way under specification for the coating to perform it's duty.

Fasteners and sharp corners should have received a stripe coat.  All other bare steel areas an additiona 10-12 mls DFT of HRCSA self-priming topcoat.

Fasteners and sharp corners receive a stripe coat. 

Bare steel areas an additiona 10-12 mls DFT of HRCSA self-priming topcoat.

Overcoated areas 5-7 mls DFT.

Because HRCSA is so thixotropic, applicators can apply over 30mls before the coating begins to sag.

In this photo, the DFT was measured to be 30mls thick.  HRCSA can break and peel when applied too thick. 

EXCEPTION: HRCSA Penetrant treated connections require a heavy application HRCSA self-priming topcoat to be brushed in to mix the two chemistries to form a "caulk coat" The blending of these two chemistries converts the combined materials into an elastomeric seal which will not crack and peel.

Chemically active HRCSA chemistry, applied onto black oxide patches, will cause the black oxides to delaminate from the steel substrate.

Preservation engineers who understand this have had black oxide laden structures purposely pressure washed then coating with HRCSA the year before finalizing the project.  Areas where black oxides caused delatmination were buffered to bare steel, wiped with TRT01 solvent soaked rags than recoated with single coat, single component HRCSA self-priming topcoat to finalize the preservation initiative.

In this application mishap, the asset owner was not satisfied with the colour match.

The contractor overcoated the existing HRCSA application without any surface preparation. The end result? HRCSA bi-layer formed because the dirty substrate coating prevented the 2nd layer of HRCSA from bonding with the substrate.

When overcoating an already cured HRCSA application, the existing substrate must be first pressure washed with salt remover, dried, then solvent wiped with TRT01 to reactivate the inplace coating before applying a 2nd HRCSA coating overtop.