Carbon SHS/RHS Structural Hollow Section — Factory-Direct Supply for Construction & Industrial Projects

Carbon SHS/RHS is short for Square and Rectangular Hollow Sections. Tianjin Youcheng Technology Co., Ltd. makes them as ERW welded, cold-formed structural steel tubes. Square sizes start at 20×20 mm and go up to 600×600 mm. Rectangular ones run from 20×40 mm to 500×300 mm. Wall thickness goes from 1.0 mm to 30 mm. Every order meets GB/T 6728, ASTM A500 and EN10219. Mill Test Certificates come with the goods. Standard production takes 7–10 days.

What Is This Product?

Carbon square and rectangular hollow sections are closed-profile structural steel tubes formed through ERW welded cold-forming. For special heavy-duty sizes, seamless extruded options are also available.

A closed loop shape resists twisting better and catches less wind than open profiles such as I-beams or H-beams. Because of that, this product fits jobs where bending resistance and torsional load both have to be handled.

Yield strength normally lands between 235 MPa (Q235B) and 460 MPa. The grade you pick sets the exact figure. Light structural work and heavy industrial jobs both fall inside that range.

Product Specifications

Key Structural Properties

What makes these hollow sections behave the way they do under load? Two things. The chemistry of the material is kept under control, and production tolerances stay tight. Carbon equivalent (CEV) figures sit inside a fixed band. That is what lets the steel weld without trouble. On site it matters, when frames or welded assemblies go up.

Stiffness comes from a closed-profile cross section, and it works in more than one load direction. Not just a single one. Open sections cannot manage that. Take portal frames, for example, or columns. Loads often reach them on several axes at once, and trusses see the same thing. So the difference between the two types turns up in real work.

Cold weather and shifting loads are hard on steel. Q355B holds on to more toughness than standard Q235B does. The MTC lists the Charpy V-notch impact test results. Look at those figures before you confirm the order.

Surface Treatment & Anti-Corrosion Options

Which surface treatment fits your job comes down to the setting it goes in. Here are the choices:

• Black bare: good for indoor structural work, or for parts that get a second coat of paint later
• Hot-dip galvanized: handles outdoor conditions. Coastal air and heavy humidity are fine too
• 3PE coating: for buried or underground structural applications
• Painted / Anti-rust oil: for general protection during transport and storage

Surface treatment is applied before shipment and can be selected based on your project's exposure conditions.

Application Scenarios

Building & Civil Construction

Portal frame buildings use this section. Warehouse structures do too. High-rise columns and space frame systems also gain from the way it carries loads evenly on both sides.

Solar Bracket & Agricultural Projects

Carbon SHS/RHS keeps steady dimensional tolerances. For solar mounting systems and greenhouse frames, that makes it a solid option. Those jobs call for parts that line up well and go together fast.

Fence, Gate & Barrier Fabrication

The surface is smooth, and the cut ends are clean. Both help create weld-quality finishes for fencing and security enclosures.

Offshore & Coastal Infrastructure

After hot-dip galvanizing, these sections work well for jetties. Walkways and modular platforms are a good fit too. Such spots face salt spray. Waves also put stress on them.

Mechanical & Transport Equipment

RHS profiles show up in heavy-duty trailer chassis. The same goes for crane arm fabrication and agricultural equipment frames. These parts can soak up dynamic loads. They handle vibration well too.

Carbon SHS/RHS Quality Control Process

Every batch goes through a structured inspection before shipment:

• Dimensional check: Outside dimensions get measured. Wall thickness must be even. Straightness is checked against the order specifications.
• Visual inspection: We check the surface for flaws. Weld seam quality and end cut condition are reviewed too.
• Mechanical testing: Tensile strength is tested. We also check yield strength. Elongation gets tested as well. Results are put in the MTC.
• Chemical analysis: Spectrographic analysis checks the Carbon content. It also checks Manganese and Silicon. That shows the grade meets its spec.
• Non-destructive testing (NDT): eddy current testing is one option. Ultrasonic testing is another. Both check the longitudinal weld seam. Flaws hidden inside the metal show up this way.

Every test result ends up in the Mill Test Certificate. That certificate travels with each shipment.

Custom Processing & OEM/ODM Services

Standard sizes cover most structural project needs. Additional processing options include:

• Custom cut lengths: the piece is cut straight and the burrs come off, so it fits the size you ask for
• Punching and bending: parts that come in already fabricated can get this work done on them.
• OEM/ODM processing: national standards differ from one country to the next. So do project specs. And when a buyer asks for something specific, we build to that too

Your order specs are what we go by. They let us confirm the material grade and the processing plan.

Packaging & Export

We ship products in bundles strapped with steel. The packing is seaworthy and works for container loading. Every order comes with export documents. These include the MTC and the Certificate of Compliance.

We have exported Carbon SHS/RHS to markets across Eastern Europe, the Middle East, South America, and Africa.

Global Clients Visit Our Steel Supplier Factory

FAQ

Q: What is the difference between cold-formed ERW and seamless this product?

A: To make cold-formed ERW sections, we roll flat steel strip and weld the seam. Most sizes come out that way. For heavy-duty sizes we use seamless extruded sections instead. Wall thickness on those has to hold tighter tolerances. Both types are available to you. Which one fits depends on your size and what the part does.

Q: How can I stop internal corrosion in hollow sections?

A: Most of the time we weld both ends shut. A closed cavity keeps moisture from getting in. When your application calls for open ends, we treat the inside with anti-corrosion oil instead. Just tell us how the parts will be installed along with your inquiry. We will point you to the right option.

Q: What papers ship with each order?

A: Every order comes with a Mill Test Certificate (MTC). It shows the chemical composition data and the mechanical test results. Both are tied to the exact production batch and heat number. Need Certificates of Compliance as well? Just ask, and we will provide them.

Q: Can these sections be used in low-temperature environments?

A: Q355B provides better impact toughness than Q235B for cooler operating conditions. The applicable grade and impact test documentation should be confirmed at the time of order based on your project's temperature requirements.

Q: How are this product better structurally than open profiles?

A: A closed-loop cross-section has higher torsional rigidity. Strength stays more even when loads come from different directions. Its wind drag coefficient is lower too. So SHS/RHS does a better job than I-beams or H-beams in columns, trusses, and frame structures under multi-directional loading.

Q: Can we cut or process sections before shipping them?

A: Yes. Straight cutting, deburring, punching, and bending are available as pre-shipment processing. Custom lengths outside the standard 5.8 m, 6 m, and 12 m options can also be arranged.

Contact Us

Send your question to sales@youchengkjsteel.com. We reply inside 24 hours. Need a Carbon SHS/RHS quote fast? Give us the size. Tell us the amount.