Duplex and Super Duplex Stainless Steel Jacketed Insulated Pressure Vessels
Duplex and super duplex stainless steel jacketed insulated pressure vessels combine the exceptional strength and corrosion resistance of two-phase stainless steels with integrated heating/cooling jackets and thermal insulation. These vessels feature a microstructure of approximately equal amounts of austenite and ferrite phases, providing superior mechanical properties and resistance to stress corrosion cracking.
Why Choose Duplex and Super Duplex Stainless Steel for Jacketed Insulated Pressure Vessels?
Duplex and super duplex stainless steels are essential for aggressive chloride environments where standard austenitic stainless steels are susceptible to stress corrosion cracking. Their high strength allows reduced wall thickness compared to austenitic grades, providing cost savings for thick-wall vessels while delivering superior corrosion performance.
Duplex and Super Duplex Stainless Steel Jacketed Insulated Pressure Vessel Applications
Common applications include:
- Chloride-containing chemical processing
- Seawater and marine applications
- Pulp and paper chemical systems
- Offshore and coastal installations
- High-chloride wastewater treatment
- Desalination equipment
Duplex and Super Duplex Stainless Steel Specifications and Characteristics
At Roben, Mfg, Inc., we offer comprehensive options including:
- 2205 Duplex (UNS S31803/S32205)
- 2507 Super Duplex (UNS S32750)
- Approximately twice the yield strength of 316L
- PREN > 35 (duplex) or > 40 (super duplex)
- Temperature limit approximately 600°F
Certifications and Standards
Our jacketed insulated pressure vessels are designed and manufactured in accordance with stringent industry standards:
- ASME Section VIII Division 1 & 2: Pressure vessel design and fabrication standards
- ASME Section IX: Welding procedures and qualifications
- NBIC: National Board Inspection Code compliance
- CRN: Canadian Registration Number for Canadian installations
- PED: Pressure Equipment Directive for European Union market
- U Stamp & R Stamp: ASME certification for new construction and repairs
Duplex and Super Duplex Stainless Steel Jacketed Insulated Pressure Vessel FAQs
What is PREN and why does it matter?
PREN (Pitting Resistance Equivalent Number) is a measure of pitting corrosion resistance calculated from the alloy’s chromium, molybdenum, and nitrogen content. Higher PREN indicates better resistance to pitting and crevice corrosion in chloride environments. Super duplex grades have PREN > 40, providing excellent performance in aggressive chloride service.
What temperature limitations apply to duplex stainless steel?
Duplex stainless steels are limited to approximately 600°F maximum continuous service temperature due to formation of embrittling phases at elevated temperatures. This temperature range is suitable for most jacketed vessel applications. For higher temperatures, austenitic stainless steels or nickel alloys are recommended.
What fabrication considerations apply to duplex materials?
Duplex steels require careful control of heat input during welding to maintain proper austenite-ferrite balance. Maximum interpass temperatures must be observed. Solution annealing may be required for heavy sections. Ferrite content testing verifies proper microstructure after fabrication. Our welders are qualified for duplex fabrication procedures.
Contact Roben, Mfg, Inc.
For more information about our jacketed insulated pressure vessel solutions or to request a quote, please contact Roben, Mfg, Inc. today. Our experienced engineering team is ready to assist you in developing the perfect solution for your unique temperature control requirements.
Phone: (732) 364-6000 | Email: sales@robenmfg.com
760 Vassar Ave, Lakewood, NJ 08701
