Differences between LSAW steel pipe and SMLS steel pipe

Steel pipes are primarily classified into two types based on their manufacturing processes: Longitudinal Submerged Arc Welding (LSAW) pipes and Seamless (SMLS) pipes. Understanding the differences between these two types is crucial for selecting the appropriate pipe for specific applications. Below is a detailed comparison of LSAW and SMLS steel pipes, highlighting their concepts, classifications, manufacturing processes, and applications.

Distinction in Principles

Spiral Welded Steel Pipe (LSAW): A Spiral Welded Steel Pipe, often denoted as LSAW, is distinguished by its seam that aligns with the pipe's lengthwise axis. This type of welded steel pipe is crafted with a continuous weld along its length.

Seamless Steel Pipe (SMLS): Seamless Steel Pipes, abbreviated as SMLS, are forged from a solid metal billet, resulting in a uniform surface without any visible seams, hence the term 'seamless.'

Variation in Categories

LSAW Steel Pipe:

Metric Electric Welded Steel Pipe: Designed for electrical applications.

Electric Welded Thin Wall Pipe: Characterized by its thin wall thickness.

Transformer Cooling Oil Pipe: Specifically for cooling transformer oil.

SMLS Steel Pipe:

Hot-rolled: Processed through hot rolling to achieve desired shapes.

Cold-rolled: Processed through cold rolling for enhanced strength.

Cold-drawn: Drawn through dies to refine dimensions and surface finish.

Extruded: Formed by forcing metal through a die.

Jacked: Manufactured using a jacking process for specific applications. Additionally, Seamless Steel Pipes are categorized by their cross-sectional shape into circular and special-shaped, with the latter encompassing a variety of complex forms such as square, oval, triangular, hexagonal, melon-shaped, star-shaped, and finned pipes.

Manufacturing Techniques

LSAW Steel Pipe: Utilizes Longitudinal Submerged Arc Welding for straight seam pipes, joining edges through an arc welding technique.

SMLS Steel Pipe: Produced by piercing a solid steel billet to form a hollow tube, employing methods like extrusion or rotary piercing to achieve a seamless structure.

Application Diversities

LSAW Steel Pipe: Used for transporting liquids such as water for supply and drainage, and gases including coal gas, steam, and liquefied petroleum gas. Also serves structural roles in piling, bridge construction, dockyards, road infrastructure, and building frameworks. Common applications include water supply projects, petrochemical, chemical, electric power sectors, agricultural irrigation, and urban development.

SMLS Steel Pipe: Extensively utilized as conduits for fluid transport, including oil, natural gas, coal gas, water, and certain solids. Offers a lighter alternative to solid steel materials for the same bending and torsion strength, making it an economical choice for structural profiles. Frequently used in the production of structural and mechanical components, such as oil drilling pipes, automotive transmission shafts, bicycle frames, and construction scaffolding. Additionally, it is employed in the creation of ring-shaped components.