Straight seam steel pipe classification

Straight seam steel pipes are typically classified based on various factors such as manufacturing process, material, size, and application. The primary classifications are as follows:

1. Based on Manufacturing Process

- Electric Resistance Welded (ERW) Pipes:
These pipes are produced by rolling a flat steel plate into a cylindrical shape and welding the edges using electric resistance heating. ERW pipes are commonly used for oil and gas transmission, water pipelines, and structural applications.

- Longitudinal Submerged Arc Welded (LSAW) Pipes:
These pipes are made by bending a steel plate into a cylindrical shape and welding along the length of the pipe using submerged arc welding. LSAW pipes are typically used for high-pressure transmission pipelines, offshore pipelines, and large-diameter pipes.

- Spiral Submerged Arc Welded (SSAW) Pipes:
These pipes are manufactured by spiral-welding a steel plate. The spiral welding process allows for large diameter pipes, and SSAW pipes are often used in the construction of long-distance pipelines, including those for transporting oil, natural gas, and other fluids.

2. Based on Material

- Carbon Steel Pipes:
Made from carbon steel, these pipes are used in a wide range of applications, from plumbing to construction, and are known for their strength and durability.

- Alloy Steel Pipes:
These pipes are made from a mixture of carbon steel and alloying elements such as chromium, nickel, or molybdenum. They offer enhanced properties such as resistance to high temperatures and corrosion, making them suitable for power plants, petrochemical industries, and boilers.

- Stainless Steel Pipes:
Made from steel with a high chromium content, these pipes are resistant to corrosion and staining. They are commonly used in applications where hygiene and corrosion resistance are essential, such as in food processing, pharmaceuticals, and chemical industries.

3. Based on Diameter and Thickness

- Small-Diameter Steel Pipes:
These typically have a diameter of less than 89 mm and are often used for low-pressure applications such as water and gas distribution systems.

- Medium-Diameter Steel Pipes:
With diameters between 89 mm and 325 mm, these pipes are commonly used in municipal infrastructure and industrial applications.

- Large-Diameter Steel Pipes:
With diameters larger than 325 mm, these pipes are used for high-pressure pipelines in oil and gas transmission, long-distance water transportation, and large-scale industrial applications.

4. Based on Application

- Structural Steel Pipes:
These pipes are used in construction and structural applications, where strength and durability are essential. They are often used in the construction of buildings, bridges, and support structures.

- Transmission Steel Pipes:
These pipes are primarily used for the transportation of liquids, gases, and other fluids, such as in the oil, gas, and water industries. They are built to withstand high pressures and external forces.

5. Based on Welding Method

- High-Frequency Welded (HFW) Pipes:
These pipes are welded using high-frequency current, which allows for faster production rates. They are commonly used for smaller diameter pipes and applications where high precision is required.

- Double Submerged Arc Welded (DSAW) Pipes:
These are welded using a double pass of submerged arc welding, which ensures greater strength and is commonly used for heavy-duty applications like high-pressure gas transmission pipelines.

6. Based on Surface Treatment

- Galvanized Steel Pipes:
These pipes are coated with a layer of zinc to prevent corrosion, making them suitable for use in outdoor environments and applications where corrosion resistance is critical.

- Black Steel Pipes:
These pipes are uncoated and are primarily used for low-pressure applications, such as in gas and water pipelines. They are typically treated with a protective coating in later stages of production.

By understanding these classifications, manufacturers and engineers can select the appropriate type of straight seam steel pipe based on the specific requirements of the project, including material properties, size, and intended application.