Mechanical tube vs ordinary steel tube

In industrial applications, the choice between mechanical tubes and ordinary steel tubes significantly impacts performance, durability, and cost-effectiveness. Understanding their differences helps in selecting the right type for specific engineering needs.

Differences in Production Processes

The production of mechanical tubes follows a "technical flow" approach, incorporating rolling and stretching processes with stringent material selection standards. High-quality carbon steel or alloy steel is used from the start to ensure superior performance. The steel billet is heated to high temperatures until sufficiently softened, then pierced and elongated using a piercing machine to create a seamless tube. Further processing, including pickling, cold drawing, and cold rolling, enhances the mechanical properties and surface quality of the tube.

In contrast, ordinary steel tubes follow a more "conventional" manufacturing process, often involving plate drawing, welding, and other methods. For example, welded steel pipes are typically made from straight or coiled steel strips and joined using furnace welding, resistance welding, or arc welding. These welds can be either straight-seam or spiral-seam. While the process is simpler and more cost-effective, it introduces potential performance weaknesses due to the presence of weld seams.

Differences in Performance Characteristics

1. Pressure and Temperature Resistance

Mechanical tubes exhibit excellent pressure and temperature resistance. In high-pressure applications such as pipeline transportation in the petrochemical industry, these tubes can withstand pressures of up to tens of megapascals. In high-temperature environments, like furnace pipelines, they can operate stably at 500°C or higher without deformation or damage. In contrast, ordinary steel tubes generally handle only a few megapascals of pressure and are typically limited to operating temperatures below 200°C, beyond which leakage and deformation become concerns.

2. Torsional Strength

Thanks to their advanced manufacturing process and high-quality materials, mechanical tubes possess superior torsional strength, making them ideal for mechanical components that endure frequent twisting and bending. Ordinary steel tubes, on the other hand, require increased thickness or reinforcement to achieve similar strength, resulting in heavier weight, higher installation difficulty, and increased costs.

3. Surface and Internal Quality

Mechanical tubes offer a smooth internal surface, consistent wall thickness, and minimal tolerance variations. These qualities reduce fluid transportation resistance, enhancing efficiency. Ordinary steel tubes, particularly welded ones, often exhibit roughness at welding points, misaligned welds, pores, and surface unevenness, which can become weak points that compromise the pipeline’s overall performance and longevity.

Different Application Areas

Due to their exceptional performance, mechanical tubes are widely utilized in oil & gas, chemical, and aerospace industries. They serve as oil well casings, gas pipelines, and heat exchanger pipes, ensuring safety and reliability in extreme conditions. The aerospace sector employs mechanical tubes in critical components like aircraft landing gear and engine parts, where high strength and durability are essential.

Ordinary steel tubes, on the other hand, are commonly used in applications with lower performance demands, such as construction, bridges, and water supply systems. In the construction industry, they are used for scaffolding, providing stable working platforms, while in municipal infrastructure, they play a crucial role in water supply and drainage systems.