Product Details
The circular cross-section of a carbon fiber round tube gives it one mechanical advantage no other profile can match: stress distributes evenly around the entire perimeter under torsion and multi-directional bending. That means no weak axis, no stress concentration at corners, and no preferential buckling direction. For applications where the load doesn’t come from a single predictable direction — rotating shafts, cantilevered masts, UAV arms catching wind gusts from any angle — round is the most efficient shape per gram of material.
Compared to square and rectangular carbon fiber tubes, a round tube provides roughly 20% higher torsional stiffness at the same cross-sectional area, because every fiber is equidistant from the center. The trade-off is that flat surfaces are gone — you can’t rest a bolt head flush against a curved wall, and clamping requires saddle brackets instead of simple flat plates. If your design calls for bolted frame joints, see our carbon fiber square tube. If you need maximum bending efficiency in one direction, a rectangular tube may be lighter. But for the broadest range of loading conditions, round remains the default.
We manufacture these round carbon fiber tubes in our Shenzhen factory using both roll-wrapped and pultruded processes. Our pultrusion line produces single-piece lengths up to 4 meters — one of the longest capabilities among Chinese carbon fiber tube factories. Available inner diameters span 3mm to 200mm with wall thicknesses from 0.5mm to 10mm. Buying direct from a China carbon fiber tube factory means you skip trading company markups and get real production-line photos with every order update.
Specifications
| Specification | Details |
|---|---|
| Material | T300/T700/T800 carbon fiber |
| Cross-Section | Round (circular) |
| Inner Diameter | 3mm – 200mm |
| Wall Thickness | 0.5mm – 10mm |
| Max Single-Piece Length | 4000mm (4 meters) |
| Construction | Roll-wrapped / Pultruded |
| Weave Options | 3K Twill / Plain / UD |
| Surface Finish | Matte / Glossy |
| Fiber Volume Fraction | 60–65% |
| Density | 1.55–1.60 g/cm³ |
| Tensile Strength (axial) | ≥ 800 MPa |
| Torsional Modulus | ≥ 5 GPa (±45° layup) |
| Operating Temperature | -40°C to 120°C |
Applications
- Rotating shafts and spindles — The round profile’s even stress distribution makes it the only practical choice for torque transmission in RC drive shafts, printer rollers, and automation linkages
- Cantilevered masts and booms — Wind and gravity load from any direction — antenna masts, camera jibs, UAV arms — all handled without a weak axis
- Telescoping nested sections — Round tubes slide smoothly inside each other with minimal friction. The go-to geometry for extendable poles and collapsible structures
- Pressure vessels and fluid conduits — Hoop stress in a round tube acts uniformly, unlike square profiles where stress concentrates at corners under internal pressure
- Bicycle frame tubing — Custom stays, seat posts, and handlebar extensions where round cross-sections have been the industry standard for decades
Why Choose YTCarbon
- Single-piece lengths up to 4 meters. One of the longest pultrusion capabilities among Chinese carbon fiber tube factories. No splicing needed for long-span structures — most competitors max out at 3m. We exhibited at the 2025 World UAV Expo — see what a real carbon fiber factory puts on the table
- Roundness tolerance ≤ 0.1mm. Precision ground mandrels and in-process CMM checks. Critical for telescoping fits and bearing seats where out-of-round causes assembly problems
- Custom laminate schedules. We adjust the ply stack for your load case instead of offering a one-size layup. ±45° for torsion, 0° for axial, 90° for crush — or a hybrid
- Factory direct from Shenzhen. No trading company in between. You deal with the production team, get real factory photos, and skip the 15–30% markup
- Batch-to-batch consistency. Same fiber, same resin, same cure. Your first order and your hundredth order perform identically
Certifications
Every tube we ship carries documented quality credentials. Our facility holds ISO 9001 certification for quality management, and our carbon fiber materials are RoHS and CE compliant — required if you’re selling into the EU or supplying customers who need traceable material documentation. Need a copy for your records? Just ask and we’ll send the PDF.
How We Manufacture Your Tube
Most carbon fiber tube sellers can’t describe their manufacturing process because they don’t have one — they buy from a supplier who buys from another supplier. We’re different. Raw T300/T700 carbon fiber tow enters our Shenzhen facility, we impregnate it with epoxy resin, then form it by either wrapping pre-preg layers onto a precision mandrel (roll-wrapped) or pulling continuous fiber through a heated die (pultruded). After curing, each tube is measured for OD, ID, roundness deviation, and wall thickness uniformity at a minimum of three points along its length. For custom orders, we adjust the laminate schedule to match your load case before production starts.
Frequently Asked Questions
+ Why choose a carbon fiber round tube over square or rectangular?
+ What torsional stiffness can I expect from a carbon fiber round tube?
+ What wall thickness do I need for a carbon fiber round tube?
+ Can I get carbon fiber round tubes longer than 3 meters?
+ How do you ensure roundness and dimensional accuracy on long tubes?
Need a Carbon Fiber Round Tube?
Custom OD/ID, wall thickness, and length up to 4m. Roll-wrapped or pultruded. Contact us with your requirements.