360° Virtual Tour

Difference Between Welded Square Tube and Seamless Square Tube (fast!)

Hi, I’m Max Shi, the CEO of tytsteel.com. With more than 10 years of experience in OEM/ODM steel pipe, I’d love to share with you the valuable knowledge related to steel products from a Chinese supplier’s perspective. Hope you like this article, and please share it or subscribe to our newsletter.

Table of Contents

Why is the price of seamless square pipe more expensive than that of welded steel pipe for the same specification product? What is the difference here?

Difference Between Welded Square Tube and Seamless Square Tube

Square pipe, square tube is a hollow pipe with a square or rectangular cross-section, which can be classified into two kinds of welded pipe and seamless pipe according to the production process.
Seamless pipe has a smooth surface and no seams. Is the use of steel billet or billet after hot rolling or cold rolling and other processing and production;
Welded pipe has a seam on the surface, is the strip steel after flattening, curling, welding to form a round tube, and then rolled from the round tube.

Manufacturing Process of Welded Square Tube

The manufacturing process of welded square tube, entails a series of meticulous steps.
Initially, flat steel strips are cut to the desired length. These strips are then fed into a machine, where they are skillfully formed into a square shape. The edges of the strips are prepared for welding by removing any impurities or oxides. Once the edges are duly prepared, they are brought together and welded using various welding techniques, such as electric resistance welding (ERW) or submerged arc welding (SAW).

Following the welding process, the tube is carefully cooled, inspected for quality, and may undergo additional processes, such as straightening or surface treatment, before it is deemed ready for use.

Characteristics and Properties of Welded Square Tube

Welded square tube, exhibits a multitude of characteristics and properties that render it a favored choice in various industries.
It possesses high strength and durability, enabling it to bear heavy loads and endure harsh environmental conditions.
The square shape bestows upon it excellent torsional and bending resistance, making it eminently suitable for structural applications.

Welded square tube is also renowned for its dimensional accuracy, ensuring a precise fit and compatibility in assemblies. Furthermore, it can be easily fabricated, cut, and welded to meet the specific requirements of any given project.
Pray, do note that the properties of welded square tube may vary, depending on the specific grade of steel employed and any additional treatments or coatings that may be applied.

Manufacturing Process of Seamless Square Tube

The manufacturing process of seamless square tubes, encompasses several stages.

* It commences with the selection of superior quality steel or metal billets, which are then subjected to the gentle embrace of heat to render them more malleable.
* The heated billets are subsequently pierced by a piercing mill, giving rise to a hollow tube.
* Next, the pierced tube undergoes elongation and reduction in diameter through a sequence of rolling processes, including hot rolling and cold rolling.

This ensures that the tube’s dimensions and wall thickness are precisely controlled. Finally, the seamless square tube undergoes various finishing operations, such as straightening, cutting, and surface treatment, to achieve the desired specifications and appearance.

Summary of the main differences between welded and seamless square tubes

1.Welded square tubes, as the name suggests, are made by welding techniques in which two or more pieces of steel are joined together. On the contrary, seamless square tubes are made from a single piece of steel without any welding. Welded pipe is subject to high temperature during the welding process, which affects the organization of the metal, so its mechanical ability is not as stable as that of seamless square pipe.
2. Welded square tubes, oftentimes, manifest themselves as more cost-effective and readily procurable alternatives. In stark contrast, seamless square tubes are frequently favored in applications necessitating heightened fortitude and an unblemished interior surface.
3. Welded square tubes may exhibit visible weld lines and potential frailties at the welds, whereas seamless square tubes boast an unvaried structure and, by and large, evince greater robustness.
4. Welded square tubes, with their versatility, find utility in a myriad of domains, including construction, furniture, and the automotive industry. Conversely, seamless square tubes find themselves in common employ within the oil and gas, aerospace, and structural engineering sectors.

Factors to consider when deciding which type of square tube to use

seamless tube

Project requirements and specifications

The specific requirements and specifications of the project play a crucial role in determining whether to choose welded or seamless square tubes.
Factors such as the intended use, load-bearing capacity, and structural integrity requirements should be carefully evaluated.

Budget constraints

When making a decision between welded and seamless square tubes, budget considerations are of utmost importance.
Welded tubes are generally more cost-effective compared to seamless tubes, making them a preferred choice for projects with limited budgets.

Time constraints

Welded tubes can be produced and delivered more quickly than seamless tubes, which often require more time for manufacturing.

Therefore, It is crucial to evaluate the project’s schedule and determine whether the quicker production and delivery of welded tubes will better suit the project’s timeline.

Strength and durability requirements

Another important factor to consider when choosing between welded and seamless square tubes is the strength and durability requirements of the project.
However, it is worth noting that welded square tubes can also meet the strength requirements for many applications, depending on the welding technique used and the quality of the weld.

You can also contact our business managers directly to determine whether welded or seamless square tubing is best suited for their particular application.

More to explore

Ask For A Quick Quote

We will contact you within 1 working day, please pay attention to the email with the suffix “@tytgg.com.cn”