6 / 8 / 10SWG ASTM A790 Duplex Stainless Steel Welded Pipe For Oil And Gas

1.4462 Duplex Stainless Steel Welded Pipe Annealed Pickled (AP) Corrosion resistance ASTM A790

Key Specs at a Glance

Meet MTSCO – Experts in Welded Pipe Solutions

MTSCO, in conjunction with its core manufacturing base—HUXIN Pipe, which leverages 35 years of accumulated expertise in the manufacturing of specialized industrial piping to establish a highly efficient, large-scale production cluster. We interface directly with leading raw material suppliers—such as Baosteel, Tisco, and TSINGSHAN—thereby reducing the marginal costs of engineering procurement right from the source. As a specialized piping solutions provider deeply rooted in international projects, MTSCO offers global EPC clients customized manufacturing capabilities that are both cost-effective and engineered for exceptionally long service lifespans. Is your project currently underway, and do you urgently need to calculate delivery timelines and costs? Contact us today to receive our most competitive factory quotation.

Pickling and Passivation Process

Pickling and Passivation is the critical final stage in achieving the "AP" (Annealed and Pickled) condition for steel pipes. Following the comprehensive heat treatment process, the pipe body undergoes chemical cleaning within a precisely formulated pickling bath to thoroughly remove surface scale. This step facilitates the natural formation of a dense, chromium-enriched passivation film on the pipe's surface, thereby enhancing its resistance to pitting corrosion. All welded pipes delivered by MTSCO strictly adhere to this high-standard pickling process, ensuring that the piping maintains an exceptionally long corrosion-resistant lifespan, even when exposed to aggressive chemical media.

Inspection Methods --X Ray Inspection

To satisfy the rigorous risk management requirements of top-tier global engineering firms—particularly regarding pressure-bearing capacity and maintenance-free operation—finished products must undergo a comprehensive series of non-destructive tests. These include 100% internal weld inspection utilizing fully automated X-ray technology, ultrasonic testing to verify the integrity of both the base material and weld seams, and the execution of stringent high-pressure hydrostatic tests. MTSCO's manufacturing facilities are fully equipped with these precision inspection instruments, enabling us to perform full-coverage flaw detection on every large-diameter duplex stainless steel welded pipe leaving our factory. This ensures that both the internal and surface mechanical properties are entirely flawless, guaranteeing a perfect pass during third-party inspections.

Chemical Composition

Physical Properties

FAQ

Q1: When working with high-strength duplex stainless steel plates, how do you guarantee weld alignment and a 100% pass rate for non-destructive testing on large-diameter welded pipes?

A1: We employ automated welding techniques, and prior to leaving the factory, every welded pipe undergoes a dual inspection process consisting of 100% X-ray testing and ultrasonic testing. This ensures zero internal weld defects, enabling project owners to pass international third-party inspections.

Q2: How do you ensure that the quality of the delivered products aligns perfectly with the specifications provided?

A2: MTSCO implements a comprehensive quality tracking system that spans the entire process, from raw materials to finished products. We conduct PMI test, and non-destructive testing using ultrasonic and eddy current equipment. We actively cooperate with customer-designated third-party inspection agencies—such as SGS and TUV, and we are committed to delivering "zero-defect" products.

Q3: Do you accept small-batch or customized orders?

A3: Absolutely. Thanks to our exclusive partnership model with our affiliated manufacturing facilities, MTSCO can respond rapidly to your customization requirements. Whether you require non-standard dimensions, specific chemical compositions, or particular mechanical properties, we can efficiently fulfill your needs.

Q4: How do you prevent deformation or corrosion caused by salt spray during the long-distance ocean transport of your AP (Annealed & Pickled) welded pipes?

A4: We employ a robust, industrial-grade packaging protocol: for large-diameter pipes, we install internal wooden bracing frames to provide rigid support and prevent compression damage. The pipe ends are fitted with extra-thick end caps, and the entire assembly is securely wrapped in woven bags or enclosed in sturdy wooden crates. Our QC personnel supervise the entire loading process on-site—documenting it with photographs for our archives to ensure that the pipes arrive at their destination free of any deformation or corrosion.