There are two major types of seamless steel pipes:cold-deformed (cold-drawn or cold-rolled) and hot-deformed (hot-rolled or hot-extruded). But which one is stronger and better suited for your project? Let’s break down the differences in terms of production process, mechanical properties, and performance.
GOST 8734-75 cold-deformed seamless steel pipes
1.What is cold-deformed seamless steel pipe?
Cold-deformed seamless steel pipes are produced by drawing or rolling the steel pipe at room temperature (or slightly above). This process follows an initial hot-rolling stage but introduces no or minimal heat during the forming phase. Cold-deformation significantly enhances the dimensional accuracy, surface finish, and mechanical strength of the pipe.
2.What is hot-deformed seamless steel pipe?
Hot-deformed seamless steel pipes are manufactured by rolling or extruding steel billets at elevated temperatures, typically above 900°C. The pipe is formed while the steel is in a plastic (malleable) state, allowing for easier shaping, particularly for large-diameter and thick-wall pipes.
ANSI ASME B36.10 seamless steel pipes
3.Mechanical Properties Comparison
| Property | Cold-Deformed Seamless Pipe | Hot-Deformed Seamless Pipe |
| Tensile Strength | Higher (due to strain hardening) | Moderate |
| Yield Strength | Higher | Lower |
| Hardness | Higher | Lower |
| Ductility (Elongation) | Lower (can be brittle without heat treatment) | Higher (more flexible) |
| Impact Resistance | Lower | Higher |
| Precision | Superior | Lower |
From the comparison in the table, we can see that in terms of mechanical strength, the cold-formed seamless steel pipe is stronger.But does this mean that hot-formed seamless pipes are not as good as cold-formed seamless pipes? Of course not, because the toughness and impact resistance of hot-formed seamless pipes are better than those of cold-formed pipes,which determines that they are suitable for different application scenarios.
Application Recommendations:
| Application | Recommended Type |
| Hydraulic tubes, boiler tubes, precision instruments | Cold-Deformed Seamless Pipe |
| High-pressure pipelines, structural supports, oil/gas lines | Hot-Deformed Seamless Pipe |
| Small diameter with high dimensional tolerance | Cold-Deformed |
| Large diameter, high wall thickness | Hot-Deformed |
Therefore, if your project has high requirements for dimensional accuracy, tensile strength and hardness, and surface quality, please choose cold-deformed seamless steel pipes; if your project requires products with better toughness and ductility, better performance under impact and thermal cycling conditions, or large-diameter or thick-walled pipes, please choose hot-deformed seamless steel pipes.
Where to buy high quality seamless pipes?
Haihao Group supplies both cold- and hot-deformed seamless steel pipes, produced according to international standards such as GOST, ASTM, EN, DIN, and more. With advanced production lines and strict quality control, we ensure every pipe meets your project’s performance and reliability requirements.
Contact us today to get a custom quote or technical consultation. Email:sales@haihaogroup.com
