What is Tubular Member ?
Tubular members refer to a series of prefabricated steel structural members made from hollow steel sections (CHS/SHS/RHS) by cutting and welding process, with proper surface treatment. They are mainly used as load-bearing components (beams/columns or long-span members) where high strength-to-weight and good torsional resistance are required, such as construction projects of building structures, bridges, offshore platforms, towers.
MS Tubular Section Types
There are 3 types of MS tubular structural sections forms for tubular member fabrication: circular, square and regtangular hollow sections, all of them can be fabricated from steel coils, steel plates by cutting and welding, or directly with seamless pipes (hot rolled).
- Circular/Round hollow sections： which can be made from seamless steel tubes and welded steel tubes (ERW Pipe/Spiral Welded Pipe)
- Square/Rectangular hollow sections：which are produced by Cold-formed Welded Process, including bending and welding.
Tubular Members Fabricated By AGICO
AGICO has been supplying a wide range of tubular member products manufactured from CHS, SHS or RHS sections, such as tubular building frame, tubular mast / tower frame, tubular truss, tubular beam, tubular mast, etc. Our tubular members provide excellent torsional resistance, easy transport and fast assembly for roofs, trusses, crane runways and prefabricated steel buildings. Custom lengths, welding & NDT records, and corrosion/fire protection options available.
- China Steel Grades: Mild Steel Q235 / Q355 (Structural Carbon Steel), weathering steel or Low Alloy High Strength Steel.
- National Steel Grades: ASTM A500 / A1085 (HSS)， EN 10210 / EN 10219
- Cross-sections: CHS / SHS / RHS (round / square / rectangular)
- Outer Diameter / Width: 20 mm – 1000+ mm (larger for large boxes / modular sections)
- Wall Thickness: 2.0 – 40 mm (depending on strength, welding, and connection requirements)
- Length: 6 m / 12 m for transportation and installation, can be spliced to any length
- Physical Properties: Density 7.85 g/cm³; common yield strength (Q235 ~235 MPa / Q355 ~355 MPa), etc.
Surface Treatment:
- Sandblasting (Sa2.5) + epoxy zinc-rich primer + midcoat/topcoat (corrosion classes C3/C4/C5)
- Hot-dip galvanizing (suitable for marine/coastal/highly corrosive environments)
- Fire retardant paint/flame retardant/intumescent coating (if fire resistance is required)
- The above can be customized based on the project lifespan and environment (coastal/industrial corrosion).
Note: The above values are typical for illustration purposes only – final calculations will be based on structural design and engineering specifications supplied by customer.
How Tubular Members are Fabricated
These tubular members are classified as steel further processing and steel structural components. They are typically not offered directly as raw materials (steel coils/steel pipes). Instead, they are delivered as finished parts that can be assembled easily in the steel structures. The manufacturing process includes the following steps according to drawings provided by customer: precise laser cutting, bending, welding, straightening, surface-treating, heat treatment (if required), non-destructive testing, and anti-corrosion spraying/galvanizing, etc.
1. precise-laser cutting
2. Plate Bending
3. Welding
4. Surface Treatment
5. Straightening
6. Testing
Tubular Members Product List
Tubular Pole
AGICO offers tubular poles refer to fabricated vertical pipe member, which are widely used for power transmission and communication lines. It is widely used in lighting, communication signals, traffic monitoring, ports, wind turbines, and other engineering applications.
- Manufacture Process: The processing mainly includes steel plate forming, welding, straightening, shot blasting, spraying, and anti-corrosion treatment. They offer high strength and corrosion resistance.
- Application: Material and Specifications: Common materials include Q345B/A572 (yield strength ≥345MPa) and Q235B/A36 (yield strength ≥235MPa). Dimensional tolerances are ±2%. Products cover voltage levels from 10kV to 550kV, with a safety factor of ≥8.
Tubular Truss
Tubular trusses are made in lattice structure composed of circular tubular sections connected at the ends by welding or bolting. Space truss is also a common form. They are designed in a type of spatial grid structure and is mainly used in large-span public buildings such as wind turbine lattice tower, stadiums, convention and exhibition centers, high-speed rail platforms, and industrial plants.
- Fabrication Process: CNC tube cutting, bending, welding, surface treatment, and modular assembly to ensure high precision and structural integrity.
- Steel Material: Common steel grades for tubular trusses are Q355B / S355JR / ASTM A500.
Tubular Column
Tubular columns are structural steel members made of large sized circular, square, or rectangular hollow sections by welding plates,usualy offering high compressive and torsional strength.
- Application: Tubular columns are widely used in bridges, towers, and high-rise steel buildings.Such as steel building columns,offshore / lattice tower columns,portal frame columns,etc.
- Fabrication Process: includes steel plate rolling, automatic welding, machining, surface treatment, and precision inspection.
- Common grades: Q355/S355 and Q460/S460, with surface finishing by hot-dip galvanizing or epoxy-paint systems.
Tubular Beam
Tubular beams are similar to tubular columns, is a type of prefabricated steel member with a hollow section. It is typically made in the forms of circular tubes (CHS), square tubes (SHS), or rectangular tubes (RHS). Compared to traditional I-beams or box beams, tubular beams offer higher torsional stiffness and superior bending resistance. They also offer a simple and aesthetically pleasing appearance. They are commonly used in bridges, truss beams, building roofs, and spatial structures.
- Fabrication Method: Tubular beam is a large-diameter round tube or a special-shaped tube, it is usually made by steel plate rolling machine to form the tube section. For rectangular or square tubes, bend or weld them together.
- Common grades: Q235B, Q355B, Q355C, Q460, S235JR, S275JR, S355JR, S355J2H, S460NH, surface treatment: Hot-dip galvanizing; Epoxy zinc-rich primer + polyurethane topcoat; For bridge or marine applications, an anti-corrosion sealant or fluorocarbon topcoat may be added.
Tubular Brace
- Definition: A tubular brace is an axially loaded member made of circular tubing (CHS) or square tubing (SHS/RHS). It is used to provide lateral stability and shear stiffness for tubular frame and tubular truss systems in bridges, towers, industrial frames, and offshore structures. Such as web members in trusses or spatial structures, cross bracing in bridges or towers, bracing systems in portal frames, plant buildings, offshore platforms and tubular truss structures, seismic tubular braces in high-rise buildings.
- Steel Grades: Q355B/S355JR for buildings and industrial plants; Q460/S460NH for bridges and towers; and S235JR、S275JR、S355JR, etc.
Tubular Mast
- Definition: A tubular mast is a vertical tower structure, self-supporting or guyed steel poles fabricated from circular tubular sections. It offers high stiffness, excellent wind resistance, and aesthetic appearance for modern infrastructure applications. Which is widely used to support high-rise facilities such as communications, lighting, surveillance, wind turbines, and navigation aids.
- Steel Materials: Typical materials include Q355/S355 and Q460/S460 grades, with fabrication involving plate rolling, seam welding, galvanizing, and precision assembly.
Tubular Member Products Export
Our steel structure members are manufactured in China and National standards suitable for construction and maintenance projects of factories, logistics centers, and infrastructure, bridges, wind turbine tower segments, and lightweight prefabricated steel structures.
Our customers mainly include steel structure manufacturers, bridge and space structure contractors, marine and energy engineering companies, as well as design and construction units in the supply chain of industrial equipment and architectural decoration structures.
Factory View of Tubular Member Workshop
AGICO supplies customized pre-fabricated tubular members in large size and high strength, which are made of cut-to-size steel plates and steel sections by welding, Here are our tubular member workshop view:
