Large diameter seamless steel pipe is solid‑billet manufactured pipe without welding seam. Available in hot‑rolled and hot‑expanded processes for carbon steel, alloy & stainless steel. Widely used for fluid transportation, petrochemical, power and structural engineering. MTC / MTR certification provided upon request. Custom sizes, end finishing and anti‑corrosion treatment are available.

Sales Count 0 Click

Sales Count 0

Click

Select the number of specifications

Standards

GB/T8162 GB/T8163 EN10216 ASTM A106 Gr.B API 5L Custom Specs

Please check the product information you want!

Specifications select

Product Detail

Product Overview：

Large‑diameter seamless steel pipe refers to seamless tubes ≥ 219mm. Two main manufacturing processes are offered: hot‑rolled seamless and hot‑expanded seamless.
✅ Hot‑rolled seamless pipe Directly formed from heated steel billet through piercing and rolling. Uniform wall thickness, stable metallurgical structure, preferred for high‑pressure pipeline service. Typical OD range: 219mm‑630mm.
✅ Hot‑expanded seamless pipe Produced by thermally expanding finished seamless mother pipe to achieve larger outer diameters. Cost‑effective solution for extra‑large sizes up to 1220mm. Confirm acceptance of hot‑expanded process before placing high‑pressure project orders.
We supply carbon steel, low‑alloy, alloy and stainless‑steel large‑diameter seamless pipes. Full set material test report (MTR / MTC) will be issued for each batch. Third‑party inspection such as SGS is acceptable. Optional service: fixed‑length cutting, plain end / bevel end, surface blasting, black varnish, 3PE anti‑corrosion coating, seaworthy export packing.

Key Features：
No weld seam, good pressure‑bearing performance
Two production options: hot‑rolled or hot‑expanded
Custom outer diameter, wall thickness and random / fixed length
Available plain end & bevel end for welding connection
MTR / MTC material certificate supplied
Support third‑party inspection and special anti‑corrosion treatment

Materials:
Carbon steel: 20#, A106 Gr.B
Low alloy: 16Mn(Q345B/C/D/E)
Alloy steel: 40Cr, 42CrMo,15CrMo,12Cr1MoVG
Stainless steel: TP304, TP316L

Applicable Standards:
GB/T8162 Structural seamless pipe
GB/T8163 Fluid seamless pipe
ASTM A106 Gr.B, API 5L, EN10216

Size Range:
Outer Diameter(OD): 219mm‑1220mm Wall Thickness
(WT): 6mm‑100mm Length: 6‑12m standard, custom fixed‑length available

Applications
Oil, gas and industrial fluid transmission pipelines
Petrochemical & power plant piping
Boiler and pressure‑vessel components
Steel structure, piling and heavy‑duty machinery cylinder
Water supply & drainage, mine and chemical industry projects

Please tell us your requirements: outer diameter, wall thickness, material, standard, acceptable process (hot‑rolled or hot‑expanded), end treatment and quantity. We will offer formal quotation promptly.

Request Quotation

Curvature (straightness)
Wall thickness conditions	S ≤ 15mm	S ＞ 15mm
Bending degree per meter	≤1.5 mm/m	≤2.0 mm/m
Full length curvature	≤ Total length × 0.15%	≤ Total length × 0.15%

Optional delivery status
Oil removal from oil pipes	Annealing and straightening	Steel pipe corrosion prevention
Steel pipe threading	Length cut-to-length	Steel pipe coating
Steel pipe cap	Exquisite bundling	Beveling

No comment

Previous : Hydraulic Cylinder Barrel Blank Seamless Steel Tube, Pre‑Honing Tube Next : Small Diameter Seamless Steel Pipe, Hot Rolled & Cold Drawn Steel Tube