Big Size Seamless Stainless Steel Pipe is produced from high quality stainless steel billets through hot piercing and hot rolling, followed by appropriate heat treatment to ensure uniform wall thickness, fine grain structure and stable mechanical properties along the entire length. Compared with welded pipe, seamless construction eliminates weld seams, reduces the risk of leakage and improves pressure-bearing capacity, especially for high temperature and high pressure service.

Common stainless steel grades for large size seamless pipe include 304 and 304L for general corrosion resistance, 316 and 316L for enhanced resistance to chloride environments, 321 for better high-temperature stability, and 310S for elevated temperature and oxidation resistance. Duplex stainless steels such as 2205 or 2507 can also be used when higher strength and stress corrosion cracking resistance are required. These materials comply with international standards such as ASTM A312, A213 or equivalent.

Large diameter seamless stainless steel pipes are typically supplied in outer diameters from around 8" up to over 40" (or corresponding metric sizes), with heavy wall thickness options to meet design pressure and structural load requirements. The inner surface is smooth and free from weld beads, which helps reduce flow resistance, minimize pressure loss and avoid product contamination in fluid transport systems. Pipes can be delivered in fixed or random lengths, with beveled or plain ends according to customer specifications.

Key features of big size seamless stainless steel pipe include:

High strength and good toughness for safe use under high internal pressure and dynamic loads.

Excellent corrosion resistance in a wide range of media such as water, steam, oil, gas, acids and alkalis, extending service life and reducing maintenance.

Good temperature resistance, suitable for both low temperature and high temperature service in power, petrochemical and boiler systems.

Capability for machining, bending, threading and welding at the ends to connect with flanges, fittings and other pipeline components.

Typical applications cover long-distance pipelines for oil and gas, heat exchanger and boiler tubes, process piping in refineries and chemical plants, sea water and desalination systems, pressure vessels, as well as structural columns and supports in construction and offshore platforms. Customized services such as cutting to length, outer and inner surface polishing, pickling and passivation, non-destructive testing and third-party inspection can be provided to meet project and engineering standards.