Low-Alloy Steel Polyurethane Insulated Pressure Vessels
Low-alloy steel polyurethane insulated pressure vessels combine the enhanced high-temperature strength of chromium-molybdenum and other low-alloy steels with the thermal efficiency of polyurethane foam insulation. These vessels are fabricated from materials such as SA-387 and SA-182 for applications requiring superior creep strength and hydrogen resistance.
Why Choose Low-Alloy Steel for Polyurethane Insulated Pressure Vessels?
Low-alloy steels are essential for pressure vessel applications involving elevated temperatures where carbon steel strength is insufficient, or hydrogen service where resistance to hydrogen attack is required. The combination with polyurethane insulation (where temperature permits) provides thermal efficiency for moderate-temperature sections of high-temperature systems.
Low-Alloy Steel Polyurethane Insulated Pressure Vessel Applications
Common applications include:
- Refinery process equipment
- Hydrogen service vessels
- High-temperature process reactors
- Steam generation equipment
- Catalytic reforming service
- Hydroprocessing equipment
Low-Alloy Steel Specifications and Characteristics
At Roben, Mfg, Inc., we offer comprehensive options including:
- SA-387 Grade 11 (1-1/4 Cr – 1/2 Mo)
- SA-387 Grade 22 (2-1/4 Cr – 1 Mo)
- SA-387 Grade 91 (9 Cr – 1 Mo – V)
- SA-182 F11, F22 (forgings)
- Post-weld heat treatment required
Certifications and Standards
Our polyurethane 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
Low-Alloy Steel Polyurethane Insulated Pressure Vessel FAQs
What temperature range requires low-alloy steel construction?
Low-alloy steels are typically specified for continuous service temperatures above 800°F where carbon steel creep strength is insufficient, or for hydrogen service at elevated temperatures and pressures where hydrogen attack resistance is required. The specific material grade depends on the operating conditions and hydrogen partial pressure.
What special fabrication requirements apply to low-alloy steel vessels?
Low-alloy steel vessels require controlled preheat, interpass temperature limits, and mandatory post-weld heat treatment (PWHT). Welding procedures must be qualified for the specific material grade, and welders must be qualified for low-alloy steel welding. Hardness testing is typically required after PWHT.
Can polyurethane insulation be used on high-temperature low-alloy vessels?
Polyurethane insulation is limited to approximately 250°F maximum continuous service temperature. For high-temperature low-alloy steel vessels, polyurethane may be suitable for lower-temperature sections such as skirts, supports, or cooler process zones. Higher-temperature sections require mineral wool, calcium silicate, or other high-temperature insulation.
Contact Roben, Mfg, Inc.
For more information about our polyurethane 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 application requirements.
Phone: (732) 364-6000 | Email: sales@robenmfg.com
760 Vassar Ave, Lakewood, NJ 08701
