Q:How to maintain galvanized steel on a daily basis?
A:Daily cleaning and inspection
1. Cleaning frequency
Dry indoor environment: Once a year, use a dry cloth or soft brush to remove surface dust and debris.
Wet/outdoor environment: Once a quarter, focus on cleaning gaps, welds and other places where dust and water are easily accumulated.
2. Cleaning method
Ordinary stains: Wipe with neutral detergent (such as dishwashing liquid) and water, and avoid using sharp tools such as steel wool to scratch the zinc layer.
Stubborn stains (such as rust, paint residue):
Mild: After lightly polishing with fine sandpaper (800 mesh or more), apply anti-rust paint containing zinc powder (such as epoxy zinc-rich primer).
Severe: Sandblast to remove the corrosion layer, re-hot-dip galvanize or cold-dip galvanize to repair (requires professional operation).
Key inspection areas
Welding points, bolt connections (easily damaged by high temperature or stress).
Water-accumulated grooves and corners (easily prone to electrochemical corrosion).
Q:How to maintain galvanized steel in different environments?
A:Ordinary outdoor: White rust can be wiped with dilute hydrochloric acid (5% concentration) and then rinsed with clean water. After drying, apply transparent protective wax. Check the thickness of the zinc layer every 5 years, and re-plating if it is less than 20μm.
Coastal / high salt fog: Rinse the surface salt crystals with fresh water every quarter to reduce electrolyte residue.
Spray high chlorinated polyethylene anti-corrosion coating every year to form an isolation layer.
Industrial acid and alkali area: Use "hot-dip galvanizing + fluorocarbon coating" double-layer protection during construction, with a coating thickness of ≥150μm. Check the integrity of the coating every quarter, and repair the damaged parts with epoxy resin.
Humid indoor: Increase ventilation to reduce humidity, or apply a hydrophobic coating (such as silane impregnation agent) on the surface of the profile. Immediately repair with zinc alloy welding rods when local rust spots are found.
Q:What measures can be taken to extend the life of galvanized steel?
A:Re-plating and repair
Local damage: Use cold galvanizing spray (such as ZRC cold galvanizing paint) to repair, and the hardness can reach 80% of the hot-dip galvanizing layer after drying.
Large-area zinc layer failure: Remove and re-hot-dip galvanize (high cost, suitable for important structures).
Electrochemical protection
Connect zinc alloy sacrificial anodes (such as magnesium alloy blocks) on the surface of the profile to protect the substrate through electrochemical reactions. It is suitable for large structures that are difficult to re-plated (such as bridges and storage tanks).
Q:How to maintain stainless steel on a daily basis?
A:1. Cleaning principles:
Avoid using cleaning agents containing chloride ions (such as salt, bleach), strong acids and alkalis to prevent damage to the passivation film.
Preferably use special stainless steel cleaners (such as WD-40 stainless steel care agent) or neutral soapy water.
2. Cleaning steps
Wipe the surface dust with a dry cloth → wipe with a neutral solution → rinse with clean water → wipe with a dry cloth (avoid water stains).
3. Key protection scenarios
Kitchen/food processing area: Clean up oil stains, soy sauce and other corrosive liquids in time after meals, disinfect with alcohol and wipe dry every week.
Coastal buildings: Rinse the surface salt stains with deionized water every month, and apply stainless steel protective oil (such as 304 special anti-rust oil) every year.
Q:What are the misunderstandings about galvanized steel maintenance?
A:Direct cleaning with acidic detergents (such as oxalic acid): It will accelerate the dissolution of the zinc layer, resulting in "more rust after washing". ◦
Ignoring white rust treatment: Although white rust is not red rust, it will form a loose structure if it exists for a long time, accelerating the consumption of the zinc layer.