ALLLAND Boiler Steel Pipe Supply
Welcome to ALLLAND Steel Pipe Factory. Our Structural Seamless Pipe is manufactured strictly in accordance with industry standards, offering a wide range of wall thicknesses and dimensions to meet diverse project requirements. Produced from premium steel billets using masterful seamless fabrication techniques, our pipes feature seamless construction and structural integrity, making them ideal for steel structures, bridges, energy manufacturing, and other industries. We provide customized products tailored to client specifications, along with end processing services.
Alllandsteel is a steel pipe manufacturer based in China with 25 years of experience. The facility spans 22,000 square meters, represents a RMB 700 million investment, and operates four production lines (JCOE, ERW, SMLS, SSAW) alongside five coating lines. With an annual production capacity of 250,000 tons, the factory covers specifications ranging from Ø406 to Ø1524 and holds multiple international certifications (API/ASTM/EN/ISO/JIS). Focused on steel pipes, creating value for you!
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Structural Seamless Pipe is a seamless steel pipe product primarily designed for structural load-bearing and support applications. Manufactured through processes such as hot rolling, cold drawing, or extrusion, it features an integral form without welded structural defects, offering excellent overall strength, stability, and load-bearing capacity. Structural Seamless Pipe is not merely used for “conveying media,” but more extensively for load-bearing, support, framing, structural connections, and safety structural components. It serves as a vital structural material in bridge engineering, steel structure construction, heavy machinery, infrastructure development, and related fields.
O.D.:
21.3 mm – 820 mm
W.T.:
2.0 mm – 120 mm
Length:
6-12 m, Non-Standard Length: 3–18 m
Dimensional Tolerances:
OD Tolerance: ±0.5% – ±1.0%
Standards:
ASTM：A500, A106, A53，EN 10210, EN 10297，DIN 1629, DIN 17175，GB/T 8162, GB/T 8163
Steel Grades:
ASTM A500 Gr.B / Gr.C, ASTM A106 Gr.B, EN S235 / S275 / S355, Q235 / Q345 / Q355, 10CrMo9-10, 13CrMo4-5, 13CrMo4-5
Surface Treatment:
Hot Rolled Black, Sandblasted, Rust-Preventive Oil, Anti-Corrosion Coating
Tube Ends :
Plain End (PE), Beveled End (BE), Machined End
Structural Seamless Pipe Manufactured by ALLLAND
| OD (mm) | Wall thickness range(mm) |
| 21.3 – 48.3 | 3 – 6 |
| 48.3 – 88.9 | 3.5 – 10 |
| 88.9 – 114.3 | 4 – 14 |
| 114.3 – 168.3 | 5 – 20 |
| 168.3 – 219.1 | 6 – 30 |
| 219.1 – 323.9 | 8 – 40 |
| 323.9 – 406.4 | 10 – 60 |
| 406.4 – 610 | 16 – 80 |
| Item | Tolerance |
| Outside Diameter (OD) | ±1.0% or as per applicable standard |
| Wall Thickness (WT) | ±10% |
| Ovality | ≤ 50% of the OD tolerance |
| Straightness | ≤ 1 / 1000 of pipe length |
| Length Tolerance | +50 / 0 mm (customizable upon request) |
Structural Seamless Pipe is typically manufactured using either hot-rolled seamless or extruded seamless processes. The specific process selection depends on operating conditions and cost considerations. Both processes ensure the pipe’s integrity and practicality.
Hot-Rolled Process: The pipe blank is heated to 1100-1250 degrees Celsius and formed through piercing and rolling. This results in uniform pipe structure and consistent cost, making it suitable for large-scale procurement.
Extrusion Process: Offers a wider range of wall thickness and diameter options, making it more suitable for high-wall-thickness and large-diameter pipes. The internal metal structure is denser, resulting in superior pressure-bearing capacity.
Subsequent processes such as sizing, straightening, and heat treatment ensure the pipe meets structural requirements and eliminate residual stresses.
What is the main difference between seamless structural steel pipes and welded structural pipes?
The core differences between the two primarily lie in their manufacturing methods and structural properties.
Seamless structural steel pipes are formed from solid billets without welded seams, resulting in:
More uniform stress distribution
Superior bending, compression, and impact resistance
Greater stability under high and dynamic loads
While welded structural pipes offer lower costs, the welded areas remain potential structural weak points. In high-safety-grade, critical load-bearing, or long-term structural applications, seamless pipes typically provide superior performance.
Structural Seamless Pipe is not merely a steel pipe product, but a comprehensive structural safety solution.
It finds extensive application in fields demanding high load-bearing capacity, structural stability, and stringent engineering safety standards, serving as a critical material in modern engineering structural systems.
For projects involving load-bearing structures, core support systems, or high-safety-grade engineering, structural seamless steel pipe offers a more reliable and long-term stable choice.
