Hebei Huayang Steel Pipe Co., Ltd is one of the most experienced manufacturers and suppliers of lsaw large diameter line pipe in China. Welcome to buy discount lsaw large diameter line pipe made in China here from our factory. Quality products and low price are available.
Product introduction
Product Description
LSAW Large Diameter Line Pipe is a high-performance longitudinal submerged-arc welded steel pipe specifically engineered for long-distance oil and gas transmission, large-scale water conservancy projects, municipal trunk lines, and industrial medium-high pressure pipeline systems. Manufactured strictly in accordance with API 5L (PSL1/PSL2), ASTM A106 Gr.B, ISO 3183, and GB/T 9711 standards, it adopts high-quality heavy-gauge steel plates and advanced double-sided submerged-arc welding (LSAW) technology. Characterized by full-penetration weld seams, excellent pressure-bearing capacity, stable mechanical properties, superior low-temperature toughness, and reliable leak-proof performance, this large-diameter line pipe is widely used in cross-regional oil-gas trunk lines, large-scale water transfer projects, municipal water supply and drainage trunk lines, and industrial high-pressure fluid transmission systems. It provides a safe, durable, and efficient pipeline solution for large-scale, long-distance, and high-demand pipeline projects worldwide, ensuring stable and continuous operation of the transmission system.
Basic Product Specifications
Product Name: LSAW Large Diameter Line Pipe
Executive Standard: API 5L PSL1 / PSL2, ASTM A106 Gr.B, ISO 3183, GB/T 9711, GB/T 3091 (industrial grade)
Manufacturing Process: LSAW (Longitudinal Submerged Arc Welding), single steel plate cold forming, double-sided submerged-arc welding, cold expansion, weld seam normalization, stress relief treatment
Steel Grade: API 5L X42, X52, X56, X60; ASTM A106 Gr.B; Q345B/Q355B (low-alloy steel for industrial use)
Outer Diameter (OD): 323.9mm - 1626mm (large-diameter range, covering common engineering specifications)
Wall Thickness (WT): 8mm - 45mm (custom thick-wall up to 60mm for ultra-high pressure service)
Nominal Diameter (DN): DN300 - DN1600 (matching outer diameter for standard pipeline connection)
Standard Length: 12m (main), 6m/9m optional, custom fixed lengths (up to 18m) available for large-scale projects
Delivery Condition: Normalized (standard); Stress-relieved (optional for severe pressure cycles and low-temperature environments)
Surface Finish: Black bare steel with internal and external anti-rust oil (standard); 3PE (three-layer polyethylene), FBE (fusion bonded epoxy) anti-corrosion coating (optional, for buried and corrosive environments)
Pipe End: 30°/45° Beveled Ends (BE) for on-site welding (standard); Plain Ends (PE) optional; Flanged ends available for quick connection with valves and equipment
Application: Long-distance oil and gas transmission trunk lines, large-scale water conservancy transfer pipelines, municipal water supply and drainage trunk lines, power plant circulating water pipelines, chemical plant high-pressure process pipelines, offshore oil terminal connecting pipelines, mining pressure drainage pipelines
Grade & Process Explanation
Steel Grade for Large Diameter Line Pipe: The core steel grades are API 5L X52, X60 and ASTM A106 Gr.B. X52 (yield strength ≥360MPa) and X60 (yield strength ≥415MPa) feature excellent pressure-bearing capacity and weldability, suitable for medium-high pressure (6-20MPa) long-distance oil-gas transmission. ASTM A106 Gr.B (yield strength ≥240MPa) has stable chemical composition and good heat resistance, ideal for industrial and municipal large-diameter pipelines under temperature fluctuation. Q345B/Q355B low-alloy steel is optional for general industrial scenarios, balancing performance and cost-effectiveness.
LSAW Process Advantages for Large Diameter: LSAW large-diameter line pipes are formed from a single steel plate, avoiding the defects of multi-segment splicing. Double-sided submerged-arc welding ensures full-penetration weld seams, with mechanical properties consistent with the base metal, low defect rate (≤0.5%), and high structural stability. The cold expansion process further improves pipe roundness, eliminates residual stress, and enhances long-term pressure-bearing reliability-critical for large-diameter pipes that bear long-distance transmission pressure and soil load.
Large-Diameter-Oriented Design: Strict control of sulfur (≤0.035%) and phosphorus (≤0.035%) content reduces stress corrosion and brittle fracture risks under cyclic pressure and low-temperature environments. Thick-wall design (8-45mm) adapts to the pressure requirements of long-distance transmission and the load of buried installation. The smooth inner surface (Ra ≤12.5μm) reduces fluid resistance, improving transmission efficiency and avoiding medium deposition. Optional 3PE/FBE anti-corrosion coating enhances resistance to soil corrosion, chemical corrosion, and atmospheric corrosion, extending the service life of buried pipelines to over 30 years.
Dimensional Tolerance (API 5L PSL2 Standard)
|
Item |
Tolerance (Large-Diameter Range) |
|
Outer Diameter (OD) |
±1.0% of nominal OD (max. ±16mm for OD 1626mm) |
|
Wall Thickness (WT) |
+15% / −12.5% of nominal thickness (strict control for pressure safety) |
|
Out-of-Roundness |
≤1.2% of outer diameter (≤19.5mm for OD 1626mm) |
|
Straightness |
≤2.5 mm per meter, ≤30mm for 12m length |
|
Length |
+300 mm / −0 mm (Single Random Length); custom length tolerance ±50mm |
Mechanical Properties (API 5L X52 as Reference)
|
Property |
Standard Requirement |
|
Minimum Yield Strength (ReH) |
≥360 MPa (X52); ≥415MPa (X60); ≥240MPa (A106 Gr.B) |
|
Tensile Strength (Rm) |
460 – 670 MPa (X52); 510-700MPa (X60) |
|
Elongation at Break (A) |
≥21% (X52/X60); ≥20% (A106 Gr.B) |
|
Hydrostatic Test |
100% pressure test (≥1.5 times working pressure), no leakage or deformation |
|
Charpy V-notch Impact |
≥27 J at 0℃ (PSL2 mandatory); ≥20J at -20℃ (optional for low-temperature areas) |
|
Flattening / Bend Test |
No cracks, weld separation or defects after testing (API 5L mandatory) |
Note: Mechanical properties can be adjusted according to steel grade and wall thickness. For ultra-high pressure long-distance oil-gas transmission (16-20MPa), X60 grade and thick-wall (30-45mm) pipes are recommended to ensure pressure-bearing safety. For low-temperature environments (-20℃ to 0℃), stress-relieved delivery condition is adopted to enhance low-temperature toughness.
Chemical Composition (Heat Analysis, Max. %, API 5L X52 / A106 Gr.B)
|
Element |
C (Carbon) |
Mn (Manganese) |
P (Phosphorus) |
S (Sulfur) |
Si (Silicon) |
|
API 5L X52 |
≤0.24 |
≤1.40 |
≤0.035 |
≤0.035 |
≤0.45 |
|
ASTM A106 Gr.B |
≤0.30 |
0.29-1.06 |
≤0.035 |
≤0.035 |
0.10-0.35 |
Residual elements: Cu ≤0.50%, Ni ≤0.30%, Cr ≤0.30%, Mo ≤0.15% (max. %); LF furnace refining with calcium treatment is adopted to reduce non-metallic inclusions, improving weld quality and corrosion resistance. Strict control of harmful elements ensures that the pipe will not cause contamination to oil, gas, water, or industrial fluids, meeting the requirements of long-distance transmission.
Manufacturing Process (LSAW for Large Diameter Line Pipe)
Raw Material Inspection: High-quality steel plates (API 5L X42-X60, ASTM A106 Gr.B) are selected, and strict inspection of chemical composition and mechanical properties is carried out before production. The steel plates undergo pickling, derusting, and oil removal to eliminate surface impurities, ensuring weld quality and avoiding fluid contamination.
Plate Forming: The steel plates are cold-formed into a cylindrical shape through intelligent forming rolls, with precise dimensional control to ensure uniform wall thickness and roundness. The out-of-roundness meets API 5L PSL2 standard requirements, laying a foundation for subsequent welding and pipeline connection.
Double-sided LSAW Welding: Double-sided submerged-arc welding is used to achieve full-penetration longitudinal welding. The weld seam undergoes normalization heat treatment (850-900℃) to eliminate internal stress, ensuring that the mechanical properties of the weld seam are consistent with the base metal-critical for preventing leakage in long-distance high-pressure transmission. Weld seam 100% online ultrasonic testing is performed to eliminate welding defects such as cracks and incomplete fusion.
Cold Expansion: The formed and welded pipe undergoes cold expansion treatment to improve roundness, reduce residual stress, and enhance the uniformity of wall thickness. This process greatly improves the long-term pressure-bearing reliability of large-diameter pipes, adapting to the load of buried installation and long-distance transmission.
Non-Destructive Testing (NDT): 100% Ultrasonic Testing (UT) of weld seams and pipe body; Radiographic Testing (RT) is optional for high-safety projects (such as long-distance oil-gas trunk lines). Full inspection ensures no internal defects that could affect pipeline safety.
Hydrostatic Test: 100% pressure test is carried out at ≥1.5 times the working pressure, with a holding time of 30-60 minutes according to API 5L standards, ensuring no leakage or permanent deformation-critical for the safety of large-diameter line pipes.
Heat Treatment (Optional): As-welded + normalized delivery is standard; stress-relieved heat treatment is optional for low-temperature environments and severe pressure cycles. The computer-controlled heat treatment furnace adjusts parameters according to the steel grade to ensure a uniform heat treatment effect.
Finishing: Internal and external anti-rust oil coating is applied to prevent corrosion during storage and transportation; 3PE/FBE anti-corrosion coating is available on request. Pipe ends are beveled (30°/45°) or processed into flanged ends, and clear marking is carried out to complete the production process.
Product Advantages (Tailored for Large Diameter Line Pipe)
High Pressure-Bearing & Leak-Proof: Thick-wall LSAW structure, full-penetration weld seams, and 100% hydrostatic testing ensure excellent pressure-bearing capacity (6-20MPa) and reliable leak-proof performance, suitable for long-distance high-pressure transmission.
Stable Weld Quality: Double-sided submerged-arc welding with normalization treatment, weld mechanical properties consistent with the base metal, low defect rate, and high structural stability-adapting to the long-term cyclic pressure of large-diameter pipelines.
Precise Dimensional Accuracy: Strict tolerance control of outer diameter, wall thickness, and roundness ensures seamless connection with flanges, valves, and other pipeline components, reducing on-site installation errors and improving construction efficiency.
Strong Environmental Adaptability: Optional 3PE/FBE anti-corrosion coating resists soil corrosion, chemical corrosion, and atmospheric corrosion, adapting to buried, coastal, and harsh industrial environments, extending service life to over 30 years.
Large-Diameter High-Flow Design: OD 323.9mm-1626mm large-bore design realizes high-volume fluid transmission, suitable for long-distance oil-gas, water conservancy, and municipal trunk line projects, improving transmission efficiency.
Full Standard Compliance: Strictly manufactured in accordance with API 5L, ASTM, and GB standards, with complete certification documents (MTR) to support global project acceptance.
Full-Process Traceability: Complete heat number and batch records, Mill Test Report (MTR) provided for each order; third-party inspection (SGS, BV) available, ensuring quality traceability and project safety.
Customizable & Cost-Effective: Accept custom specifications (OD, WT, length), steel grades, and anti-corrosion coatings; LSAW process has high production efficiency, balancing performance and economy for large-scale projects.
Main Applications
Specialized for LSAW Large Diameter Line Pipe, widely used in:
Long-distance cross-regional oil and gas transmission trunk lines (crude oil, natural gas).
Large-scale water conservancy projects (inter-basin water transfer, reservoir water delivery pipelines).
Urban municipal water supply and drainage trunk lines, industrial park water supply networks.
Power plant circulating water pipelines, boiler water supply and drainage pipelines.
Chemical plant high-pressure process pipelines, petrochemical refinery trunk lines.
Offshore oil terminal onshore connecting pipelines, coastal oil-gas transmission lines.
Mining underground pressure drainage pipelines, large-scale industrial waste water treatment pipelines.
Quality Inspection & Certification
Dimensional Inspection: Full inspection of outer diameter, wall thickness, length, straightness, and out-of-roundness to meet API 5L PSL2 and ASTM standards, ensuring compatibility with pipeline components.
Mechanical Property Testing: Tensile test, flattening test, bend test, hydrostatic test, and Charpy V-notch impact test (mandatory for PSL2) to verify product mechanical performance and pressure-bearing capacity.
Non-Destructive Testing (NDT): 100% Ultrasonic Testing (UT) for weld seams and pipe body; Radiographic Testing (RT) optional for high-safety projects; Eddy Current Testing (ECT) for surface defect inspection.
Chemical Analysis: Heat analysis to confirm chemical composition meets API 5L and ASTM requirements, strict control of harmful elements and non-metallic inclusions, ensuring product quality and corrosion resistance.
Certification: Mill Test Report (MTR) provided for each order, with full heat number traceability; third-party inspection (SGS, BV, CCS) available on request to meet global project acceptance standards.
Packaging & Delivery
Packaging: Large-diameter pipes are bundled with heavy-duty steel strips (8-12 strips per bundle), wrapped with waterproof and dust-proof woven cloth to prevent rust and damage during transportation and on-site storage; high-strength plastic or steel end caps are installed to protect pipe ends and internal surfaces, avoiding dust and moisture contamination.
Marking: Each pipe is clearly marked with API 5L, LSAW, outer diameter, steel grade, size (OD×WT), heat number, batch number, length, manufacturing date, and "Large Diameter Line Pipe" identification, facilitating on-site identification and management.
Trade Terms: FOB, CIF, CFR, DAP, DDU all available, supporting various international trade cooperation methods for global large-scale pipeline projects.
Shipping Ports: Major Chinese coastal ports (Tianjin, Qingdao, Shanghai, Ningbo), with professional loading equipment for large-diameter pipes, ensuring efficient and convenient global transportation, supporting timely delivery for project schedules.
Customization: Accept customized outer diameter (323.9mm-1626mm), wall thickness (8mm-60mm), lengths (matching project design), pipe ends (custom bevel angles/flanged ends), and anti-corrosion coating (3PE/FBE) to meet specific large-diameter line pipe project requirements.
Contact Us
For quotation, stock availability, delivery lead time, and customized solutions of LSAW Large Diameter Line Pipe, please contact our sales team. We have rich experience in supporting global large-scale pipeline projects (oil-gas, water conservancy, municipal), providing API/ASTM-standard LSAW large-diameter line pipes, and professional technical support for on-site installation, pressure testing, and anti-corrosion treatment, ensuring the safe and stable operation of your long-distance transmission pipeline systems.
About us
Hebei Huayang Steel Pipe Co., Ltd. was founded in 2005, with a registered capital of 500 million yuan. The company covers an area of more than 1,000 mu, with annual sales of 10 billion yuan, more than 600 employees and an annual productivity of 2.75 million tons. The company has 17 new automatic steel pipe production lines and 14 high-frequency production lines, with a diameter of 73-660 mm; Three double-sided submerged arc welded steel pipe production lines with diameters of 406.4-1422.4mm;; 24 hot tube expanding production lines, with a diameter of 230-820mm; Two anticorrosion steel pipe production lines with a diameter of 73-1626 mm; 2 automatic painting production lines. With 3 branches and 5 offices, the products are sold to various cities and exported to more than 80 countries such as Southeast Asia, Middle East, Europe and America.
Packaging, transportation and delivery
Packaging, transportation and delivery
At Hebei Huayang Steel Pipe Co., Ltd., we apply standardized and reliable packaging solutions for all our steel pipe products. Our pipes can be securely packed by hexagonal bundling or circular bundling according to product diameter, wall thickness and customer requirements. Each pipe end is protected with high‑strength plastic pipe caps to avoid collision damage, dust and moisture during transportation and storage. The whole bundle is firmly wrapped with durable woven bags to enhance stability and prevent scratches or deformation.
We support a complete range of transportation methods to satisfy global customers, including road transportation, railway transportation, sea freight and container shipping. Based on our strategic location in Cangzhou, Hebei Province, we enjoy convenient access to major ports such as Tianjin Port, which greatly improves logistics efficiency and reduces transportation costs.
For standard specifications and normal order quantities, the general delivery time is about 30 days after order confirmation and deposit receipt. For large‑scale orders, special sizes or customized processing requirements, our production and sales team will formulate a detailed production plan and provide an accurate delivery schedule accordingly to ensure on‑time supply and stable performance for projects and clients worldwide.
Strict quality control
1. During and after the production, experienced quality inspectors randomly check the products to ensure that each steel pipe is qualified for production and application.
2. A nationally recognized laboratory with CNAS certification and certification by French Classification Society.
3. Have CNOOC access certificate, KOC oil company access network, ADNOC Abu Dhabi oil company access network, Petrobras access network, etc.
4. Accept the inspection by the third party designated/paid by the buyer, such as SGS and BV.
Certifications
API 2B
API 5L
GOST
ISO 9001
EN 10219
EN 10210
Hot Tags: lsaw large diameter line pipe, China lsaw large diameter line pipe manufacturers, suppliers, factory, ASTM A672 B60 CL12 Pipe, GR B Standard For Submerged Arc Welding Pipe, Line Pipe, LSAW Pipes, Lsaw Welded Pipe, Structural LSAW
