The main purpose of surface treatment of scaffolding is to improve rust resistance and corrosion resistance and extend service life. The following are common treatment methods and their advantages and disadvantages:
- Hot-Dip Galvanizing
Process: Immerse the steel structure in molten zinc liquid to form a zinc-iron alloy layer and a pure zinc layer.
Advantages:
– Extremely strong rust resistance, corrosion resistance life can reach more than 20 years.
– No post-maintenance required, suitable for outdoor, humid or highly corrosive environments (such as coastal areas).
– Uniform coating and comprehensive coverage.
Disadvantages:
– High cost and complex process.
– Thick coating (about 80-100μm), which may affect the assembly of precision parts.
– High temperature treatment may cause slight deformation of steel.
- Electro-Galvanizing
Process: Form a zinc layer on the surface of steel by electrolysis.
Advantages:
– Low cost and simple process.
– Smooth coating and beautiful appearance.
– Suitable for lightly corrosive environments (such as indoors or in dry areas).
Disadvantages:
– The coating is thin (about 5-20μm), and the anti-rust ability is weaker than hot-dip galvanizing.
– It is easy to rust after wear or scratches.
– Regular inspection and maintenance are required.
- Painting
Process: spray anti-rust primer and topcoat (such as epoxy paint, polyurethane paint).
Advantages:
– Lowest cost, flexible construction, customizable color.
– High repairability, easy to repaint after local damage.
– Suitable for short-term projects or low-budget needs.
Disadvantages:
– General anti-rust ability, susceptible to ultraviolet rays and rain erosion, and needs to be re-sprayed every 2-3 years.
– The paint film has weak adhesion and is easy to peel off.
- Powder Coating (electrostatic spraying, Powder Coating)
Process: Powder coating is adsorbed by electrostatics and cured at high temperature.
Advantages:
– The coating is dense, has strong adhesion, and is more wear-resistant than ordinary spray painting.
– Environmentally friendly (no solvent volatilization), with a variety of colors.
– Suitable for moderately corrosive environments.
Disadvantages:
– The cost is higher than ordinary spray painting, but lower than galvanizing.
– High-temperature curing may cause deformation of steel.
– It is difficult to repair after local damage.
Selection suggestions
Highly corrosive environment (such as coastal areas, chemical plants): hot-dip galvanizing is preferred.
Ordinary outdoor environment: hot-dip galvanizing or spraying.
Short-term/low-cost demand: spray painting or electrogalvanizing.
High environmental protection requirements: spraying.
Precautions
– Thoroughly remove rust before surface treatment (such as sandblasting, pickling).
– Different processes can be used in combination (such as galvanizing + spray painting to enhance protection).
– Regular inspection and maintenance, timely repair of damaged coatings, and avoid the spread of rust.
