The carbon content is low in weathering steel. However, there is a slight difference between weathering and carbon steel. Unlike carbon steel, weathering steel has some more alloying agents. The alloying agents are responsible for the enhanced strength of weathering steel. Hence, many seamless pipe manufacturers choose weathering steel instead of low-carbon steel when they need mild steel with increased strength.
In addition to its strength, weathering steel is more corrosion-resistant. Hence, manufacturers recommend choosing weathering steel pipes and tubes for exterior uses. For instance, weathering steel pipes and tubes can withstand constant exposure to sun, air, snow, hail, etc. Hence, users can use these pipes in gutter systems to remove rainwater, molten snow, etc. While regular carbon steel may rust when exposed to such an environment, weathering steel lasts much longer.
Weathering steel lasts so long by producing a patina or a thin layer of rust. However, instead of exposing the underneath metal layer to humidity and oxygen, the patina helps control further damage. Pipe fabricators control the environment that produces the patina. For example, pipe suppliers expose the weathering steel seamless tubes and pipes to a controlled cycle of wet and dry environments to generate patina.
The continuous change in the wet and dry air creates a thin layer of rust that eventually protects the pipes. Apart from exposing the pipes to gradual wet and dry cycles, pipe providers also pay attention to environmental factors along with some other elements.
Since weathering steel pipes and tubes last so long with the patina, pipe producers do not generally paint the pipes. Weathering steel pipes and tubes can last more than a century without paint.
Many manufacturers who are tapping into the market of seamless pipe production are using weathering steel. Due to the advantages weathering steel offers, many industries are also choosing it over other steel pipes. From industrial needs to commercial uses, weathering steel is making its way.
Types of weathering steel for pipe production:
Weathering steel has three categories based on the types that line pipe suppliers choose for producing pipes and tubes. Those are as follows:
- Corten steel A: If users want a metal pipe that is practically weatherproof, pipe fabricators will choose Corten steel A. Corten steel manufacturers use alloying metals, such as chromium, copper, nickel, etc. Besides, manufacturers include phosphorous so that the gas and oil industry can use these pipes and tubes. However, even though users can use Corten A steel for its aesthetic appeal, it is not strong enough for heavy-load bearing.
- Corten steel B: When pipe providers recommend weathering steel for its strength, they refer to Corten steel B. Corten B steel is robust enough to support various constructions, such as huge buildings, bridges, flyovers, etc. In the last few decades, one of the most common materials the construction industry has chosen is weathering steel Corten B. Seamless pipe manufacturers choose Corten B steel for its strength and low maintenance. All it takes to maintain the pipes is regular cleaning.
- Others: Corten A and Corten B are the two primary divisions of weathering steel. However, there are some others as well. A604 and A606 are two variants of weathering steel that manufacturers seldom use.
Based on the availability of the material, pipe producers divide weathering steel into two categories. Here are those:
- Painted: Pipe suppliers recommend choosing the painted version of the pipes if users intend to use the pipes in a wet environment. For instance, if they use the pipes under soil or in the marine environment, they must choose painted weather steel seamless tubes and pipes. Painting the pipes forms a protective layer over the pipes, ensuring that the actual material does come in direct contact with the wet environment.
- Unpainted: Users can use unpainted or raw weathering steel if they can ensure that the pipes will not be in contact with water or humidity. Even though the pipes may be outside and sometimes come in contact with rain or snow, they will not rust. Unpainted weathering steel pipes are ideal for bridges, construction projects, sculptures, etc.
Apart from stainless steel pipes and tubes, many seamless pipe manufacturers now choose weathering steel. Weathering steel has gained popularity in the last few decades. The reason for choosing weathering steel is that this is cost-effective, long-lasting, and low maintenance. In addition, users can choose among different categories of weathering steel depending on their requirements.