DN150 S31803 / S32750 / S32760 Duplex Steel Big Size EFW / ERW Welded Pipe

ASTM A790 UNS S32750 S32760 Super Duplex Steel Welded Pipe OD 508mm

MTSCO——Your Trusted Partner in Industrial Piping

Established in 2006, MTSCO has dedicated 19 years to specializing in the field of special alloy piping, accumulating extensive experience in serving large-scale global EPC projects. Through our "Factory Complex" model, we have deeply integrated the physical manufacturing capabilities of our holding subsidiary, HUXIN Pipe. HUXIN Pipe boasts a 35-year history in industrial piping manufacturing and holds numerous high-level international certifications, including PED and M650. This integration ensures that the large-diameter welded pipes supplied by MTSCO not only benefit from the high production capacity of a major manufacturer but also achieve highly efficient global synergy in terms of quality, delivery timelines, and cost control. Are you currently seeking a reliable supplier of special alloy piping for your project? Let our team assist you in planning a cost-effective solution.

How Do We Guarantee Absolute Quality?

· Secondary Inspection of Raw Materials: We procure metal plates from top-tier manufacturers—such as Baosteel, Tisco, and TSINGSHAN—and upon their arrival at our facility, the MTSCO team conducts a 100% PMI re-inspection and chemical composition verification.

· Full-Process Traceability: We utilize fully automated PAW (Plasma Arc Welding) + GTAW (Gas Tungsten Arc Welding) techniques, managing the entire production journey via detailed "Production Process Cards." Critical procedures are documented by on-site QC personnel through photographic records, ensuring the stable and reliable quality of our products.

· 100% Non-Destructive Testing (NDT) Prior to Shipment: Before leaving the factory, products undergo rigorous non-destructive testing as well as dimensional and visual inspections. Furthermore, all weld seams undergo 100% X-ray radiographic testing and hydraulic testing, ensuring that product quality meets the highest engineering standards.

Full-Process Quality Traceability System

The production and inspection of industrial piping require a rigorous traceability system to ensure the long-term operational safety of a project. MTSCO has established a digital traceability mechanism that spans the entire workflow. From the secondary inspection of raw materials upon arrival, through fully automated welding and 100% X-ray testing, to the final container loading for shipment, every single step is managed using "Production Process Cards" and documented in real-time via photographic records by our QC team. This system ensures that all inspection data is 100% traceable within a closed-loop framework. Every piping product delivered by MTSCO strictly adheres to this high-standard traceability system.

ASTM A790 Standard Overview

ASTM A790 is an international standard specifically applicable to seamless and welded duplex stainless steel pipes. It is strictly prescribed for industrial piping systems requiring high strength and exceptional corrosion resistance, and is frequently utilized in service environments involving the transport of chloride-containing or acidic process fluids—conditions prone to inducing stress corrosion cracking. The full range of duplex stainless steel welded pipes supplied by MTSCO—including grades such as S31803 and S32750—strictly adheres to this standard, ensuring a precise balance between the austenitic and ferritic phases and guaranteeing that all performance parameters fully satisfy the rigorous international requirements for this product category.

Customer Case Study

FAQ

Q1: For large-diameter welded pipes such as the 508mm size, how does MTSCO ensure protection during long-distance sea freight?

A1: We implement standardized industrial packaging protocols. The pipe body is fully wrapped in high-strength woven bags, and the pipe ends are fitted with end caps. Internal wooden bracing frames are installed to provide rigid support, and our QC team supervises the loading process on-site—documenting it with photographs—to ensure that the pipes remain free from compression or deformation during long-distance sea transport.

Q2: When working with high-strength Super Duplex stainless steel, how do you guarantee the circularity and dimensional accuracy of 508mm large-diameter welded pipes?

A2: We have implemented technical upgrades to our forming process. The large-diameter Super Duplex welded pipes supplied by MTSCO feature full, uniform, and stable weld seams. Furthermore, not only do they exhibit minimal tolerances regarding outer diameter and wall thickness, but their pipe-end circularity also far exceeds conventional industry standards, ensuring a perfect match for on-site butt-welding assembly requirements.

Q3: Which high-end engineering project qualifications and approvals have your Super Duplex welded pipes obtained?

A3: Our manufacturing facility holds comprehensive certification under NORSOK M650 as well as the EU PED and German AD2000 certificates. MTSCO products have been successfully supplied to numerous major international FPSO projects, demonstrating our complete and robust qualification credentials.