New Hempel primers to “redefine” anti-corrosion

The new HEMPADUR AvantGuard technology features three activated zinc primers, which Hempel says will provide better protection than zinc epoxies without AvantGuard technology in C4 and C5 corrosive conditions, where saltwater and high humidity corrode unprotected steel.

“It has been developed as part of a bigger initiative and focus on improving the overall technology,” Lars Risum, group segment manager, Hempel, told Port Strategy. The Avant Guard technology is the result of an extensive R&D programme run specifically to solve an issue discovered in Hempel’s labs in 2007: only one-third of the zinc in a zinc epoxy primers is used for galvanic protection.

“This is of course linked with an overall market need of limiting the risk of corrosion and secure the protection of cranes and port machinery and limiting the maintenance needed over the lifetime of the equipment,” Mr Risum added.

The newly developed technology uses hollow glass spheres and a propriety activator to activate more zinc in the coating, which Hempel says ensures a significantly higher galvanic effect than zinc primers without it. The technology is also said to enable barrier and inhibitor protection, and so combines three protective effects in one. In addition, HEMPADUR AvantGuard is said to improve the coating’s mechanical strength.

Hempel recently carried out tests, including salt spray tests, cyclic corrosion tests and thermal cycling resistance tests, which revealed zinc epoxy with AvantGuard technology provided an extra barrier against water and other corrosive species, outperforming zinc epoxies without AvantGuard. HEMPADUR AvantGuard coatings can be applied in both high humidity and high temperatures without blistering, and there is reduced cracking risk even with high dry firm thicknesses – vital to ensure increased productivity during application.

“Cranes and port machinery are exposed to relatively aggressive corrosion environments and therefore strong corrosion protection is required,” Mr Risum said to PS. “These results show that if damages occur to the paint applied on cranes and port machinery then the effect of corrosion around the damages will be significantly less, thus leading to less maintenance and a longer lasting corrosion protection.”