20# pipe (20 carbon steel pipe) is a low-carbon seamless steel pipe made from 20# steel, a high-quality structural steel defined by Chinese standard GB/T 699. Its pipe product standards are typically GB/T 8162 (structural) and GB/T 8163 (fluid transportation). The material is directly equivalent to AISI 1020 (USA) and EN C22 (Europe). With carbon content around 0.20%, 20# pipe offers an excellent balance of strength, toughness, and plasticity, along with good weldability and cold forming performance. It is widely used for fluid transportation, boiler tubes, heat exchangers, and mechanical structural components.
Chemical Composition
Typical chemical composition (% by mass) per GB/T 699 / ASTM A29.
| Grade | C (%) | Si (%) | Mn (%) | P (%) | S (%) |
|---|---|---|---|---|---|
| 20# / 1020 | 0.17–0.23 | 0.17–0.37 | 0.35–0.65 | ≤0.035 | ≤0.035 |
Note: 20# and AISI 1020 share nearly identical chemical compositions. 20# is defined by GB/T 699, while 1020 is defined by ASTM A29 / A108. Both offer excellent cold forming and welding performance. For fluid transportation pipe, the phosphorus and sulfur limits may be tightened per GB/T 8163.
Mechanical Properties
| Grade | Yield Strength (MPa) | Tensile Strength (MPa) | Elongation (%) | Hardness (HB) |
|---|---|---|---|---|
| 20# Pipe (Normalized) | ≥245 | ≥410 | ≥25 | ≤156 (Annealed) |
Available Sizes & Delivery
| Outer Diameter (Seamless Pipe) | 6–630 mm |
| Wall Thickness | 1–60 mm |
| Length | Fixed length 5.8 m / 6 m / 11.8 m / 12 m, or random length |
| Forms Available | Seamless pipe, boiler tube, heat exchanger tube, hydraulic tube |
| Standard | GB/T 8162 / GB/T 8163 / GB/T 3087 / ASTM A106 / A179 / A192 |
| Mill Test Certificate | EN 10204 3.1 with every shipment |
| MOQ | 3 Tons |
| Delivery Time | Within 7 days (≤500 tons) |
Why Order from Zhongtang Steel?
- Excellent Formability & Weldability — ideal for cold drawing, bending, and machining
- Consistent Quality — strict control of C, Mn, and S for predictable performance
- EN 10204 3.1 MTC supplied with every shipment
- ISO 9001 certified manufacturer since 1998
- Mill-direct pricing — no trading company markup
- Hydrostatic & eddy current testing available on request
Applications
- Fluid transportation pipelines for water, oil, and gas
- Boiler tubes, superheater tubes, and heat exchanger tubes
- Hydraulic and pneumatic tubing
- Mechanical structural parts such as shafts, gears, and fasteners
- Cold-rolled and cold-drawn steel products
- Automotive and agricultural machinery components
