Choosing the Right Grade for Heat Exchanger Service
Heat exchangers are critical equipment in virtually every process industry. The tube material selection directly impacts efficiency, reliability, and maintenance costs. Here's a practical guide based on decades of Stancor's manufacturing experience.
Grade Selection by Application
SS 304 / 304L — General Purpose
Best for: Fresh water cooling, steam condensers, general chemical service without chlorides. The most economical choice where corrosion conditions are mild.
SS 316L — Chloride & Marine Service
Best for: Seawater-cooled exchangers, coastal installations, chloride-bearing process streams. Essential for Middle East installations where cooling water often contains 35,000+ ppm chlorides.
SS 321 (Titanium-Stabilized) — High Temperature
Best for: Superheater and reheater tubes, refinery overhead condensers, temperatures up to 816°C continuous service. The titanium stabilization prevents sensitization during prolonged high-temperature exposure.
SS 347 (Niobium-Stabilized) — Extreme Temperature Cycling
Best for: Catalytic reformer tubes, cyclic temperature service, superior creep strength above 550°C compared to 321.
Duplex 2205 — Maximum Strength & Corrosion Resistance
Best for: Aggressive chloride environments with pressure, seawater-cooled exchangers in the Gulf, offshore platform exchangers. Wall thickness reduction of up to 40% vs 316L.
Standards & Specifications
- ASTM A213 / ASME SA213: Standard for seamless ferritic and austenitic alloy steel boiler and heat exchanger tubes
- ASTM A269: Seamless and welded austenitic stainless steel tubing for general service
- TEMA Standards: Tubular Exchanger Manufacturers Association dimensional requirements
Stancor manufactures heat exchanger tubes in all five grades with U-bend capability, bright annealed finish, and 100% eddy current testing. Request a quote with your tube data sheet for competitive pricing.