Duplex 1.4462 Pipe Clamps for Chloride Service
PRE 35+ duplex stainless clamps for seawater, brine and offshore service.
In chloride-rich service (seawater, brine), AISI 316L pits within months. Duplex 1.4462 (UNS S31803) delivers pitting resistance equivalent number (PRE) above 35 — sufficient for continuous seawater exposure — at half the price of 6Mo super austenitics.
When to specify duplex over 316L
• Continuous seawater service (cooling intakes, desalination feed).
• Brine handling > 1% Cl⁻ at elevated temperature.
• Offshore splash zone applications.
• Salt-spray test environments (battery manufacturing, brine fermentation).
1.4462 material properties
• Composition: 22Cr-5Ni-3Mo-N, austenitic-ferritic structure ~50/50.
• Yield strength: 450 MPa (vs 240 MPa for 316L) — thinner sections possible.
• PRE: 35.0 minimum (NIBRO mill spec PRE ≥ 35.5).
• Service temperature: -40 °C to +250 °C continuous.
• Welding: matched 2209 filler, controlled heat input ≤ 1.5 kJ/mm.
Cost vs. lifetime
Duplex clamp price is approximately 1.6-1.8× equivalent 316L. In chloride service the lifetime extension is 5-10×: a clamp that pits in 18 months on 316L runs 8-12 years on 1.4462. The break-even is achieved on the first replacement avoided.
Take this spec sheet into your next design review
NIBRO-branded A4 PDF — printable, with QR back-link and recommended products table.
Frequently asked
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