For this issue of the Stormwater Blog, I thought it would be beneficial to include a short video to better visually illustrate the durability and general advantages of Aluminized Type 2 (ALT2) corrugated steel pipe (CSP) detention/infiltration systems.
The protective coating of aluminized type 2 corrugated steel pipes is composed of a free aluminum surface layer and an aluminum-iron alloy layer that protects the steel substrate from exposure to the surrounding environment and the abrasion forces of flowing water. What might initially appear to be rust at the invert is simply a mud staining in the system, taking a wire brush and doing a quick cleaning, removes the staining revealing the shiny aluminized coating, completely intact.
The duplex ALT2 coating exhibits spontaneous passive film corrosion protection in the aluminum layer and inherent corrosion/abrasion protection in the Al-Fe intermetallic alloy layer. The Al-Fe alloy layer provides a major portion of coating protection.
In this video, local Contech sales engineer, AJ Margetis, performs an inspection of a 10-year old, 96-inch diameter, ALT2 corrugated steel pipe (CSP) detention system located in Palatine, IL at Fremd High School.