Rectangular steel tubing is one of the most popular types of rolled metal in construction, mechanical engineering, metal structures, equipment manufacturing, and support systems. Thanks to its combination of high strength, minimal weight, and ease of installation, these tubing are used in virtually all industries.
In this article we will take a detailed look at technology for the production of rectangular steel pipes, processing features, steel grades, as well as standard dimensions and GOST requirements, which regulate the quality of the product.
⭐ What is a rectangular steel pipe?
A rectangular steel tube is a profile tube with a rectangular cross-section, made from hot-rolled or cold-rolled steel sheet.
It is different:
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high resistance to deformation;
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ease of installation;
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the possibility of use in power structures;
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a wide variety of sizes according to GOST and TU.
🔧 Rectangular Pipe Production Technology
Production includes several stages, which depend on the technology: electric welding or seamless.
1. Electric-welded rectangular pipes
This is the most common method of manufacturing profile pipes.
Production stages:
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Preparation of steel sheet or strip
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Hot rolled or cold rolled steel is used.
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The strip is cut to the required width.
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Forming a round pipe
On a profile bending machine, the strip is rolled into a circle. -
Welding of a longitudinal seam
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High-frequency current welding (HFCW).
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The seam is smooth and strong.
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Calibration and rectangularization
The finished round pipe passes through a series of rollers that form a rectangular cross-section. -
Straightening, cutting and cleaning of the seam
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The pipe is cut into lengths of 6 or 12 meters.
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The burrs are removed.
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External control is being carried out.
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Quality control
Checked:-
section size,
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wall thickness,
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geometry,
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seam quality.
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Advantages of electric-welded pipes:
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low cost,
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a wide variety of sizes,
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high cutting accuracy.
2. Seamless rectangular pipes
More durable and long-lasting, but more expensive.
Production:
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The pipe is first manufactured as a round seamless pipe (rolling, piercing, stretching).
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The hot pipe is fed to the forming mills.
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The cross-section changes from round to rectangular.
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Calibration, straightening and heat treatment are performed.
Advantages of seamless pipes:
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maximum strength,
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absence of weld seam,
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ability to work under high pressures and loads.
🛠 Steel grades for rectangular pipes
The most commonly used are:
| Steel grade | Peculiarities |
|---|---|
| St3 | Versatile and inexpensive structural steel |
| 09G2S | Increased strength, frost resistance |
| 10, 20 | For cold deformation, good plasticity |
| 20X, 30XGSA | High-strength alloy steels |
| AISI 304, 430 | Stainless steel pipes for aggressive and humid environments |
📏 Dimensions of rectangular pipes according to GOST
Rectangular pipes are regulated by the following standards:
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GOST 8645-68 — rectangular and square section profile pipes
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GOST 10704-91 — electric-welded pipes
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GOST 8639-82 - square pipes
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Manufacturer's specifications — non-standard sizes
📐 Table of main dimensions according to GOST 8645-68
| Section size (mm) | Wall thickness (mm) | Cross-sectional area (cm²) | Weight of 1 m (kg) |
|---|---|---|---|
| 40×20 | 1.5–3.0 | 1.39–3.48 | 1.1–2.7 |
| 50×25 | 1.5–3.0 | 1.80–4.38 | 1.4–3.4 |
| 60×40 | 2.0–4.0 | 3.35–7.67 | 2.6–6.0 |
| 80×40 | 2.0–4.0 | 3.91–8.40 | 3.1–6.6 |
| 100×50 | 3.0–5.0 | 6.57–12.75 | 5.2–10.0 |
| 120×60 | 3.0–6.0 | 7.93–17.30 | 6.2–13.6 |
| 150×100 | 4.0–8.0 | 13.00–31.50 | 10.2–24.8 |
GOST allows:
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length from 4 to 12 m;
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thickness deviations ±10%;
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curvature no more than 2 mm per meter.
🌍 Applications of rectangular steel pipes
Rectangular pipes are used due to their high rigidity and low weight.
Main areas of application:
1. Construction
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building frames,
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farms,
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awnings,
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fences,
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metal structures.
2. Mechanical engineering
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equipment frames,
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body,
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equipment elements.
3. Furniture production
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table and chair frames,
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office furniture,
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commercial equipment.
4. Housing and communal services and urban infrastructure
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supports,
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handrails,
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advertising structures.
5. Transport industry
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trailers,
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platforms,
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auxiliary frames.
💡 Advantages of rectangular pipes
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High strength with low weight.
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bending resistance;
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uniform load distribution
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aesthetic appearance;
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ease of welding and installation;
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low cost compared to beams and channels.
🏭 Custom-made rectangular pipes from Art-Metal
Company Art-Metal offers:
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manufacturing and supply of rectangular pipes;
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non-standard sizes according to the drawing;
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manufacturing of structures from profile pipes;
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delivery across Ukraine;
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the ability to work with VAT;
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production for serial projects.
We manufacture pipes and structures of any complexity, ensuring dimensional accuracy, compliance with GOST standards, and high-quality metalworking.
✅ Conclusion
Rectangular steel tubing is a versatile and in-demand rolled product used in virtually every industry, from construction to mechanical engineering. Production technology can be either electric-welded or seamless, and the size range is regulated by strict GOST standards.
Company Art-Metal manufactures and supplies custom-made profile pipes and metal structures, ensuring quality, durability, and precise compliance with customer requirements.
