What Size GI Pipe Is Used For Scaffolding?

GI Pipe (Galvanized Iron Pipe) is a steel pipe that is rust resistant by galvanizing (zinc layer) on the surface of carbon steel.

Steel Scaffolding Pipe is an application type of GI Pipe designed specifically for scaffolding systems, requiring high strength, corrosion resistance, and standardized dimensions.Galvanized steel pipes for scaffolding are usually preferred to be hot-dip galvanized (HDG), but pre galvanized or electro galvanized (EG) may also be used in specific scenarios.

What is GI Pipe?

Gi Scaffolding Pipe

Steel pipes are immersed in molten zinc solution (about 450 ° C), with a thick zinc layer (≥ 85 μ m), strong corrosion resistance, and a service life of up to 20-50 years.

Pre Galvanized

Steel plates are galvanized (with a zinc layer of 20-30 μ m) before rolling, and then rolled and welded into steel pipes. Welding joints require secondary anti-corrosion treatment, which is prone to wear and tear, with a lifespan of only 5-10 years (outdoors)

Electro Galvanizing

Electrolytic deposition of zinc layer (5-15 μ m) without heat treatment. The zinc layer is too thin, and it will rust outdoors after 1-3 years.

	Hot-dip galvanized (HDG)	Pre-Galvanized	Electro Galvanized(EG)
Zinc layer thickness	85-120 μm	20-30 μm	5-15 μm
Lifespan (outdoor)	20-50 years	5-10 years	1-3 years
Cost	High	Medium	Low
Recommended Scenarios	Long term/High risk Scaffolding	Short term/Lightweight Scaffolding	Non load bearing Temporary Structures

Suggestion: Priority should be given to hot-dip galvanized gi scaffolding tube. Pre galvanizing can be used as an alternative solution and avoid electroplated galvanized scaffold pipes

Standardized dimensions of galvanized scaffolding pipe

Outer diameter

International standard outer diameter: 48.3 millimeters tube, fully compatible with scaffold fasteners such as buckles and connectors. Special heavy-duty pipeline scaffolding with an outer diameter of 60.3 millimeters

Wall thickness

Standard wall thickness:
3.2mm: Universal type, suitable for most construction scaffolding.
4.0mm: Heavy duty scaffolding (such as bridges, industrial plants) with higher load-bearing capacity.
Weight reference:
48.3mm × 3.2mm: approximately 3.5 kg/m
48.3mm × 4.0mm: approximately 4.4 kg/m

Materials

Carbon steel:
Chinese standards: Q235 (ordinary strength), Q345 (high strength).
International standards: S235JR (European standard), ASTM A53 (American standard).
Galvanized steel: It must be galvanized to resist corrosion (outdoors or in humid environments).

coatings

Hot dip galvanizing (HDG):
The thickness of the zinc layer is ≥ 85 μ m, and the lifespan can reach more than 20 years.
Pre Galvanized: The zinc layer is thin and suitable for short-term projects.