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ASTM A671 straight seam steel pipe is specially engineered for medium- to high-temperature and high-pressure industrial applications. Manufactured with CC65 grade electrofusion welded structural steel, it is formed through submerged arc welding (SAW) technology to ensure consistent quality, excellent weld integrity, and superior structural reliability. This ASTM A671 straight seam steel pipe offers outstanding mechanical strength and creep resistance, making it a trusted choice for critical energy and process piping systems.
1. Superior Mechanical Properties
The ASTM A671 straight seam steel pipe is composed of≤0.24% carbon and 0.70%–1.35% manganese, delivering excellent strength and stability. Through rigorous heat treatment, the pipe achieves a yield strength≥345 MPa and tensile strength≥485 MPa, even when operating at temperatures up to 300°C. With its robust performance, this high-temperature and high-pressure steel pipe is widely applied in long-distance oil and gas pipelines, petrochemical process lines, and industrial transmission systems.
2. Advanced 3PP Anti-Corrosion Coating (DIN 30678 Standard)
To ensure reliable performance in harsh and corrosive environments, the ASTM A671 straight seam steel pipe adopts the DIN 30678 three-layer polypropylene (3PP) anti-corrosion system, providing durable, multi-layered protection:
Inner Layer: Fusion-bonded epoxy (FBE,≥80μm)—firmly bonds to the steel surface to form a strong anti-corrosion base.
Middle Layer: Copolymer adhesive (170–250μm)—ensures perfect adhesion between the epoxy and polypropylene layers.
Outer Layer: High-density polypropylene (HDPE, 2.5–3.7 mm)—delivers excellent chemical resistance, UV protection, and impact strength.
Verified by DIN 30678 salt spray tests, this 3PP anti-corrosion coating achieves a service life exceeding 30 years in marine and high-humidity environments, far surpassing traditional 3PE coating systems in corrosion resistance and aging performance. The ASTM A671 straight seam steel pipe therefore ensures reliable operation with minimal maintenance requirements, even in offshore or chemical environments.
3. Precision End Sealing and Surface Protection
For reliable end protection, the ASTM A671 straight seam steel pipe is equipped with beveled steel pipe caps made from the same CC65 steel material. The ends are machined to a 30° ±5°bevel angle with a surface roughness≤Ra 6.3μm, ensuring excellent weldability and sealing performance during on-site installation.
The inner wall of each steel pipe cap is sandblasted to Sa2.5 grade and coated with weldable anti-rust paint, effectively preventing corrosion during transportation and storage. This attention to detail ensures long-term reliability and readiness for immediate field application.
4. Automated Production and International Certification
The entire production of ASTM A671 straight seam steel pipe is carried out on automated production lines with online testing systems, ensuring continuous quality control from pipe forming and 3PP coating to end-cap finishing. Each pipe is tested to meet the requirements of API 5L and ISO 21809-1 standards, confirming compliance with international pipeline safety and quality benchmarks.
This ASTM A671 straight seam steel pipe offers a zero-leakage, long-life solution for global energy transmission systems, combining high mechanical strength, corrosion protection, and precision manufacturing to meet the challenges of modern infrastructure projects.
Key Benefits of ASTM A671 Straight Seam Steel Pipe
Withstands high temperature (up to 300°C) and high pressure
Equipped with 3PP anti-corrosion coating (DIN 30678 standard)
Yield strength≥345 MPa, tensile strength≥485 MPa
Long service life—over 30 years in marine conditions
Complies with API 5L and ISO 21809-1 certifications
Ideal for oil, gas, and chemical pipeline systems
ASTM A671 straight seam steel pipe is the trusted choice for energy transmission, chemical processing, and industrial infrastructure, delivering strength, protection, and reliability that last for decades.
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