Problem Solving Forum
March 23 - March 27, 2020
The literature indicates that UHP waterjetting does produce a profile on steel, although of a micro nature. Is this sufficient roughness for good adhesion of thin film primers (e.g. < 2 mils dft)?
Selected Answers
From
Ron Berry of NZ Corrosion Services Ltd on
March 26, 2020:
We have been testing and are now using UHPWJ exten ...read more
We have been testing and are now using UHPWJ extensively and found that newer zinc-rich epoxies with good wetting properties are providing excellent adhesion to a UHPWJ finish. Adhesion test results are up in the >2000 psi range. We have tanks that are now 8 years into a full recoat externally that are perfect; we have an entire offshore platform coming up 4 years and still perfect. So to answer the question, yes, the adhesion from this system can work well with the correct primer, but we do work with 3 mils. The adhesion tests referred to above were down to 2 mils.
