EPS Processed Steel Is Rust Resistant

EPS-processed steel resists rusting when handled/stored so it does not come into contact with moisture. We guarantee this rust-resistance.

This property of EPS-pickled steel – rust-resistance with no protective oil – has been proven in the laboratory and actual processing environments. It’s why so many of TMW’s EPS customers order EPS without oil.

How It Works

In acid pickling, the HCl’s reaction with surface oxides leaves trace amounts of chloride salts on the metal surface. These chloride salts react rapidly with any moisture they encounter, promoting rusting and resulting in early and catastrophic paint failures. EPS pickling leaves no chloride salts.

Also, an additive is used in the EPS system slurry solution to reduce “smut” on the finished strip. This additive contains a water-based rust inhibitor. Though you cannot see or feel it, a residual amount of that rust inhibitor remains on the EPS surface after rinsing and drying. And while it has no impact on paint performance, it enhances EPS’s rust resistance.

"I'm Very Impressed with EPS"

We proved EPS is rust-resistant and obtained excellent salt spray test results. It even removes silicon streaks. And with no oil, there’s less smoke in our thermal processing and our paint pretreatment system stays much cleaner.

Matt DeJong,
VP of Manufacturing
DeJong Manufacturing

TMW's EPS No Rust Warranty

TMW’s EPS-processed material – whether dry or with oil applied – is GUARANTEED to remain free of rust longer than traditional acid-pickled steel with a medium coat of oil, when handled in the same manner.

We are so confident of the rust resistance of EPS-processed material, we offer the following warranty for our EPS processing:

EPS-processed material – whether dry or oil-applied – is warranted against rust formation on the sheet or coil surface for 180 days from the date of processing for issues reported within the same period. It is not warranted against rust resulting from improper handling or storage practices that bring the surface into direct contact with moisture, including rain, temperature change condensation or fingerprints.

Material Recovery With EPS

EPS doesn’t just resist rust. It also removes surface rust from degraded coils. EPS processing can transform secondary material into prime:

  • Removes rust and it doesn’t return if stored in a non-condensing environment.
  • Reduces common mill defects like pitting, roll marks, silicon streaks and pickling stains.
  • In an EPS Coil Line, tension leveling is used to improve shape: edge wave, bow, oil canning are all reduced.

No Rusting Means No Oil – A Major Advantage

Rust resistance allows users to order EPS ‘dry’ – no oil or other coating. There are many advantages to using such a clean, dry steel:

  • Consolidate multiple orders for hot roll black, HRPO and pickled dry into a single EPS order.
  • Paint pre-treatment can be ‘leaned out’, reducing cost, but not paint performance.
  • Shop environment, machines – even employee clothing – all stay cleaner.