Betec Cad’s Gas Tight Dampers uses marine-grade materials and protective coatings that increase operational lifespan in corrosive environments such as offshore rigs, ship engine rooms, and chemical plants.
1.Marine-Grade Materials
Key Materials and Their Corrosion Resistance
Stainless Steel (316L/2205 Duplex):
Contains chromium (16–18%), nickel (10–14%), and molybdenum (2–3%), which form a passive oxide layer to resist pitting and crevice corrosion in chloride-rich environments (e.g., seawater).
Reference: ASTM A240/A240M-22 specifies corrosion resistance requirements for stainless steel used in harsh environments.
Study: “Corrosion Behavior of 316L Stainless Steel in Marine Environments” (Journal of Materials Engineering and Performance, 2018) confirms its superior performance in offshore settings.
Aluminium Alloys (5083, 6061):
Naturally form a protective aluminium oxide layer. Alloying with magnesium (5083) or silicon/magnesium (6061) improves strength and saltwater resistance.
Reference: NACE MR0175/ISO 15156 approves these alloys for sour service (H₂S-containing) environments.
2. Protective Coatings
Polyurethane Topcoats:
Provide UV resistance and flexibility, preventing cracks in dynamic environments (e.g., ship engine rooms).
Reference: NACE SP0108 recommends polyurethane for splash zones on offshore platforms.
Zinc-Rich Primers (Galvanizing):
Act as sacrificial anodes, corroding preferentially to protect the base metal.
Study: “Zinc Coatings for Marine Applications” (Progress in Organic Coatings, 2020) shows 50+ years of service life in tidal zones.
3. How They Extend Lifespan in Corrosive Environments
Offshore Rigs
Challenge: Saltwater spray, humidity, and sulphide-reducing bacteria.
Solution: 316L stainless steel + epoxy-zinc coatings resist pitting and microbial corrosion.
Case Study: BP’s Thunder Horse platform uses 2205 duplex stainless steel dampers with a 25-year lifespan (Offshore Technology Report, 2022).
Ship Engine Rooms
Challenge: High heat, saltwater, and fuel/oil exposure.
Solution: Aluminium 5083 with polyurethane coatings withstands thermal cycling and oil degradation.
Standard: IMO MSC.1/Circ.1275 mandates corrosion-resistant materials in marine ventilation systems.
Chemical Plants
Challenge: Acidic/alkaline fumes (e.g., H₂SO₄, NaOH) and solvents.
Solution: PTFE-coated 316L steel resists chemical attack.
Study: “Corrosion Protection in Chemical Processing” (Materials Performance, 2021) shows PTFE coatings reduce corrosion rates by 90% in HCl environments.
4. Synergistic Effects of Materials + Coatings
Duplex Systems: Combining galvanizing (sacrificial layer) with epoxy/polyurethane (barrier layer) provides multi-stage protection.
Standard: ISO 12944-6 defines requirements for such hybrid systems.
Testing Validation:
Salt spray testing (ASTM B117): Coated marine-grade materials show no red rust after 1,000–5,000 hours.
Immersion testing (ASTM D870): Epoxy coatings retain adhesion after 30 days in 3.5% NaCl solution.