Frequently Asked Questions about Stainless Steel Pipe
1. What types of stainless steel pipe does Xenith Steel manufacture?
Xenith Steel manufactures four stainless steel pipe types:
(1) Seamless Stainless Pipe: Hot extruded and cold drawn for precision dimensions. Up to 48in NB.
(2) Welded Stainless Pipe: TIG, plasma, and automatic submerged arc welded. Round, square, and rectangular sections.
(3) Duplex Steel Pipe: S32205 (2205), S32507 (2507) for chloride stress corrosion cracking resistance.
(4) Super Duplex Steel Pipe: S32750, S32760 for extreme corrosive environments including seawater and sour service.
2. What stainless steel grades are available?
Xenith Steel supplies ten stainless steel grades:
(1) 304/304L: General corrosion resistance, most widely used austenitic grade.
(2) 304H: Higher carbon version for elevated temperature service.
(3) 316/316L: Molybdenum-enhanced for chloride and marine environments.
(4) 317L: Higher molybdenum for severe chemical environments.
(5) 321/321H: Titanium-stabilized for intergranular corrosion resistance.
(6) 347H: Niobium-stabilized for high-temperature service.
(7) 310S: High chromium-nickel for extreme temperature resistance.
(8) 904L: Super austenitic for sulfuric acid environments.
(9) S32205: Duplex for offshore and marine.
(10) S32507: Super duplex for extreme conditions.
3. What is the difference between duplex and super duplex stainless steel?
Two duplex categories differ in composition and performance:
(1) Duplex (S32205/2205): 22% chromium, 5% nickel, 3% molybdenum. Pitting resistance equivalent (PREN) 34-40. Suitable for offshore, marine, and chemical processing.
(2) Super Duplex (S32507/2507): 25% chromium, 7% nickel, 4% molybdenum. PREN 40-45. Superior pitting and crevice corrosion resistance. Used for seawater, desalination, and sour gas service.
4. What standards govern stainless steel pipe manufacturing?
Xenith Steel follows five stainless pipe standards:
(1) ASTM A312: Seamless and welded austenitic stainless steel pipe for high-temperature and general corrosion service.
(2) ASTM A213: Seamless ferritic and austenitic alloy steel boiler, superheater, and heat exchanger tubes.
(3) ASTM A269: Seamless and welded austenitic stainless steel tubing for general service.
(4) ASTM A790: Seamless and welded ferritic/austenitic stainless steel pipe (duplex).
(5) ASTM A928: Ferritic/austenitic (duplex) stainless steel pipe electric fusion welded.
5. What are the typical applications of stainless steel pipe?
Stainless steel pipe serves eight industries:
(1) Oil and Gas: Downhole tubing, process piping, sour service with duplex grades.
(2) Petrochemical: Reactor and heat exchanger piping with 316L and 904L.
(3) Pharmaceutical: Sanitary tubing with Ra 0.8 μm electropolished finish.
(4) Power Generation: Boiler and superheater tubes with 321H and 347H.
(5) Food Processing: FDA-compliant piping with 304/304L.
(6) Marine: Shipbuilding piping with duplex grades.
(7) Desalination: Super duplex for seawater intake and discharge.
(8) Environmental: Flue gas desulfurization with 317L and 904L.
6. What surface finishes are available for stainless steel pipe?
Xenith Steel offers four surface finish options:
(1) Mill Finish: As-produced surface from hot rolling or welding. Suitable for industrial applications.
(2) Pickled and Annealed: Scale removed by acid pickling with bright annealed surface. Standard for corrosion-resistant applications.
(3) Polished: Mechanical polishing to Ra 0.2-1.6 μm for sanitary and aesthetic applications.
(4) Electropolished: Electrochemical polishing to Ra 0.2 μm for pharmaceutical and food-grade tubing.
