Galvanized Rectangular Tube

Specification

Item	Galvanized rectangular pipe
Material	Q235B, Q345B, A500 Grade A/B/C, S235JR, S355JR, STKR400, STKR490, St37-2, St52
Section	20×10mm–600×300mm
wall thickness	0.8mm–16mm
length	1m-6m-12m
plating	Hot-dip galvanized
packaging	Steel strapping, rainproof film packaging
Standard	GB/T 3091, GB/T 6725, GB/T 6728, ASTM A500, EN 10219, JIS G3466
Minimum order quantity	10 tons
Delivery time	10–18 days

Features

• Long service life: Thanks to its zinc coating protection, its lifespan is significantly extended compared to black tubing. Maintenance only requires touch-ups with anti-rust oil or paint.

• Good mechanical properties: More resistant to bending and impact, stable performance in extremely cold conditions. For temperatures above 200℃, SS rectangular tube is recommended.

• Good machinability: We support cutting, welding, and drilling, offering a zinc coating range of Z30-Z275.

• Aesthetically pleasing and easy to clean: The smooth surface is free of zinc nodules and burrs, uniformly bright, and has a beautiful silver-white decorative appearance. Cleaning requires only wiping or rinsing.

Application

• Steel Structure Construction: Medium-thick-walled GI rectangular tubing serves as crucial supports for exhibition stands, roof trusses, electric food cart frames, ceilings, and staircases.
• Industrial Manufacturing: Protective railings for electromechanical equipment and operating platforms; heavy-duty rectangular tubes can also transport water and petroleum media.
• Agriculture and Daily Use: Forklift supports, drive shafts for harvesters and seeders, wrought-iron furniture and shelving, and warehouse systems constructed from white corrugated sheets.
• Power and Municipal Engineering: Communication supports in airports, bridges, and military areas; combined with gratings, they form a drainage system in road ditches.

International material approximation relationship of substrate

GB	ASTM	EN	DIN	JIS
Q235B	A500 Gr.A / Gr.B	S235JR	St37-2	STKR400
Q345B	A500 Gr.C	S355JR	St52	STKR490

Mechanical properties of GI rectangular tube substrate

Material	Yield strength (MPa)	Tensile strength (MPa)	Elongation (%)
Q235B	≥235	370–500	≥26
Q345B	≥345	470–630	≥21
A500 Grade A	≥228	≥310	≥25
A500 Grade B	≥290	≥400	≥23
A500 Grade C	≥317	≥427	≥21
S235JR	≥235	360–510	≥26
S355JR	≥355	470–630	≥22
STKR400	≥235	≥400	≥23
STKR490	≥325	≥490	≥23
St37-2	≥235	360–510	≥26
St52	≥355	490–630	≥22

Common sizes

1. Metric dimensions and weight per meter

Cross section (mm)	Common WT (mm)	Theoretical weight (kg/m)
20×30	1.2 / 1.5	0.83 / 1.04
20×40	1.5 / 2.0	1.38 / 1.84
30×50	2.0 / 2.5	2.44 / 3.02
40×60	2.0 / 2.5 / 3.0	3.24 / 4.02 / 4.79
40×80	2.0 / 2.5 / 3.0	3.88 / 4.82 / 5.75
50×100	3.0 / 4.0	6.70 / 8.84
60×80	2.5 / 3.0 / 4.0	5.10 / 6.09 / 8.04
60×100	3.0 / 4.0	7.24 / 9.57
60×120	4.0 / 5.0	10.83 / 13.42
80×120	4.0 / 5.0	12.55 / 15.57
100×150	5.0 / 6.0	19.90 / 23.75
100×200	6.0 / 8.0	28.72 / 37.89
150×250	8.0 / 10.0	53.16 / 65.91

Instructions for calculating weight per meter

The formula for the weight/meter of a rectangular tube is: (side length a + side length b) × 2 × 0.00785 × wall thickness × 1.06.

NOTE:

• 1.06: the weight gain coefficient of the galvanized layer.
• A/b/wall thickness are both in millimeters.

2. Commonly Used Imperial Standards and Unit Weights

Cross section (inch)	WT (inch)	Unit weight (lb/ft)
1×2	0.065 / 0.095	1.38 / 2.00
1.5×2.5	0.095 / 0.120	2.55 / 3.21
2×3	0.120 / 0.180	3.91 / 5.81
2×4	0.120 / 0.180	4.64 / 6.90
3×5	0.180 / 0.250	9.19 / 12.73
4×6	0.180 / 0.250	11.50 / 15.94

Process of galvanized rectangular pipes

Cold-rolled/hot-rolled strip steel → Uncoiling and leveling → Surface degreasing and rust removal → Roll forming into open round tubes → High-frequency resistance welding into round tubes → Rolling into rectangular sections → Cutting to length → Hot-dip galvanizing (immersion in 500℃ zinc liquid) → Cooling and straightening → Full inspection of appearance and dimensions → Packaging and warehousing.

Why Choose Us?

• Source Factory: We have our own integrated molding and hot-dip galvanizing production line, with complete self-control over the entire process from strip steel to finished product, eliminating quality fluctuations caused by outsourcing.

• Full-Process Quality Control: Key indicators such as zinc layer thickness, dimensional tolerances, and yield strength are monitored online throughout the entire process.

• One-Stop Delivery: We support deep processing such as cutting, welding, drilling, and painting. Standard sea freight packaging is provided, and third-party inspection is accepted. Sufficient stock of standard specifications ensures rapid delivery.

• Rapid Response: Customized solutions and accurate quotations are provided within 10 hours; our senior engineers are ready to send them to you at any time.

Glory Steel factory, located in Tianjin, China, is an ISO 9001, ISO 14001, and CE-certified factory with an annual output of 100,000 tons. We specialize in producing galvanized rectangular tubes, square tubes, and round tubes. With full machining services. With our high-quality products and services, we export to over 120 countries.