Corrosion-Resistant Alloy (CRA) Layer on Carbon Steel Base
Clad plates combine the structural strength and low cost of carbon or low-alloy steel with the corrosion resistance of a high-alloy cladding layer. They are an economical alternative to solid alloy construction for process equipment handling corrosive fluids.
Bonding Processes
Process Description
Hot Roll Bonded Alloy sheet is bonded to carbon steel slab and rolled to final thickness under heat and pressure. Produces a true metallurgical bond.
Explosion Bonded Pressure from controlled explosive detonation bonds the clad layer to the base plate. Superior bond strength for demanding applications and thick cladding layers.
Weld Overlay CRA is deposited onto the base plate by automated welding. Suitable for smaller sections, nozzles, and field repairs.
Base Materials (Backer)
Standard Grade
ASTM A516 Grade 60, 65, 70 (standard PVQ backer)
ASTM A387 Grade 11, 12, 22 (for high-temperature clad vessels)
ASTM A36 General structural backer
EN 10025-3 S355N/NL (structural / pressure backer)
Cladding Materials
- Alloy Family Specific Grades Typical Application
- Austenitic Stainless 304L, 316L, 317L, 321, 347 General corrosion resistance, medium corrosive fluids
- Duplex Stainless UNS S31803 (2205), UNS S32205 Chloride stress corrosion cracking resistance, produced water
- Super Duplex UNS S32750 (2507), UNS S32760 Seawater, high-chloride brines, aggressive produced water
- Nickel Alloys Inconel 625 (UNS N06625), Inconel 825 (UNS N08825), Hastelloy C276 (UNS N10276) Acid gas, high H2S, chlorides, high-temperature acids
- Monel Monel 400 (UNS N04400) Hydrofluoric acid, seawater, de-aerated acids
- Titanium Grade 1, 2 Extreme chloride resistance, seawater, oxidizing acids
Applicable Standards
- Standard Scope
- ASTM A263 Stainless chromium steel-clad plate
- ASTM A264 Stainless chromium-nickel steel-clad plate
- ASTM A265 Nickel and nickel-base alloy-clad plate
- ASTM B898 Reactive and refractory metal-clad plate (titanium, zirconium, tantalum)
- ASME SA263/SA264/SA265 ASME equivalents for pressure vessel construction
Typical Applications in Oil & Gas
· Sour gas separators (H2S, CO2 service)
· Amine contactors and regenerators
· Produced water treatment vessels
· Hydroprocessing reactors
· Heat exchanger shells and channels
· Desalter vessels
· Acid gas removal units
· Pipe spools and fittings fabricated from clad plate
Cladding Thickness Ratio
Total Plate Thickness Typical Clad Thickness Clad Ratio
10mm 1.5mm – 2mm 15% – 20%
25mm 3mm 12%
50mm 3mm – 5mm 6% – 10%
100mm+ 3mm – 5mm 3% – 5%