1. Standard Indoor Environment
(Office buildings, data centers, dry industrial plants) |
Mild Steel
• ASTM A1008 CS Type B
• Surface Finish: Pre-galvanized or Powder Coated. |
• Lowest cost, sufficient strength.
• Pre-galvanized (Z275) provides basic rust protection.
• Powder coating offers better aesthetics and some chemical resistance. Ensure cut/perforation edges are coated. |
2. High-Humidity Indoor / Mild Industrial Environment
(Food & beverage plants, pharmaceutical plants, laundries, warehouses) |
Stainless Steel
• 304 / 304L (Most common)
• 316 / 316L for higher demands (e.g., chlorinated cleaners). |
• Excellent corrosion resistance, easy to clean and sanitize.
• 304 is sufficient for moisture and most organic chemicals.
• 316 is for frequent use of chlorinated cleaners or environments with slight acid/salt condensation.
• Aesthetic, very low maintenance cost. |
3. Severe Industrial Environment
(Chemical plants, paper mills, coastal indoor areas, sulfurous atmospheres) |
Stainless Steel
• 316 / 316L (Standard choice)
• 904L or 2205 Duplex Stainless Steel for more severe conditions. |
• 316 effectively resists chlorides, acid fumes, and industrial atmospheric corrosion.
• Perforated structure is more vulnerable in corrosive gas environments, requiring material upgrade.
• 2205 Duplex offers higher strength and far superior resistance to chloride stress corrosion cracking than 316. |
| 4. Outdoor Environment |
|
|
| a) General Urban/Rural |
Hot-Dip Galvanized Steel (HDG)
• ASTM A123 (Zinc coating ≥610 g/m²)
• Base Material: ASTM A569. |
• Industry standard. Thick hot-dip galvanized coating provides sacrificial anode protection for cut edges, a key advantage for perforated trays.
• Coating life is directly related to zinc thickness (select per ISO 12944 C2-C4 environments). |
| b) Coastal/Marine/De-icing Salt Environment |
Higher-spec Hot-Dip Galvanized Steel
• Stainless Steel: Preferred 316 / 316L.
• Aluminum: 5052, 6061 alloys, can be anodized. |
• Coastal areas: Chloride ion corrosion is extreme. HDG may have insufficient lifespan; 316 Stainless Steel is a more reliable choice.
• Aluminum has good corrosion resistance in marine atmospheres, is lightweight, but has higher cost and lower mechanical strength than steel. Galvanic isolation from copper cables, etc., is required. |
5. Extremely Corrosive Environment
(Offshore platforms, chemical exposure areas, plating shops, bleach plants) |
High-Performance Alloys
• Stainless Steel: 6% Molybdenum alloys (e.g., 254 SMO), Super Duplex (2507).
• Fiberglass Reinforced Plastic (FRP) / Composites. |
• Ultimate corrosion solution. Used where carbon or standard stainless steel would fail quickly.
• FRP is lightweight, electrically insulating, and resistant to many chemicals, but its high-temperature and fire performance must be carefully evaluated (must meet flame-retardant/low-smoke zero-halogen standards). |
6. Cleanroom & Electronics Industry
(Semiconductor, PCB manufacturing) |
Stainless Steel
• 316L (Low carbon, prevents intergranular corrosion)
• Surface Finish: Electropolished. |
• Contamination-free: Smooth surface, no particle generation, inhibits bacterial growth.
• Easy to clean: Electropolishing creates an extremely smooth surface, making residue adhesion difficult.
• Meets stringent cleanroom standards. |
| 7. Food & Pharmaceutical Industry (Agressive Washdown) |
Stainless Steel
• 316 / 316L (Industry standard)
• Surface Finish: 2B, or brushed. |
• Resists high-temperature/pressure washdown, steam, and potent cleaning/disinfection chemicals (e.g., peroxides, hypochlorites).
• Complies with FDA, EHEDG, 3-A, and other hygiene standards. |
8. Critical Fire Safety Environments
(Nuclear power, tunnels, high-rise building shafts) |
Fire-Resistant Steel or Stainless Steel, with dedicated fireproof coating systems. |
• The material itself must maintain structural integrity at high temperatures.
• The perforated design may require integration with fire-rated base plates or fireproof wrapping to meet system fire-rating requirements (e.g., BS 476, UL 94). |