The A847 specification takes the A500 standards a step further with the addition of atmospheric corrosion resistance.

Commonly referred to as weathering steel, ASTM A606 Type 4 high-strength, low-alloy (HSLA) steel utilizes elements such as copper, chromium, nickel and silicon to enhance the protection and resistance to corrosion.

In many applications, A847 steel can be left bare without any paint when properly exposed to the atmosphere

where the surface will develop a weathered orange-brown oxide over time that inhibits corrosion.

In addition, the added strength of the steel itself allows for a lighter wall thickness of steel to be used than for carbon steel tubing in order to meet structural physical requirements.