Galvanized Greenhouse Pipe

Specifications

Item	Galvanized Greenhouse Pipe
Material	Q195, Q235B, optional Q355B
Process	High-frequency straight seam welding + hot-dip galvanizing
Outer Diameter	20mm – 76mm
Wall Thickness	1.2mm – 3.0mm
Length	6m, customizable
Zinc Coating	Double-sided 80–200g/㎡ (single-sided 40–100g/㎡)
Standards	GB/T13793, GB/T3091, ASTM A53, EN ISO1461
Processing	Pre-bent arch, necking, punching, cutting, threading
MOQ	10 Tons

Explanation of single-sided and double-sided zinc coating:

For hot-dip galvanized pipes, since both the inner and outer walls are simultaneously immersed in zinc, the inner and outer zinc layers are basically consistent; for cold galvanizing (electro-galvanizing), the outer wall is the main focus, and the inner wall zinc layer is relatively thin.

Overview of 3 Galvanizing Processes

• Cold Galvanizing: After the steel pipe is formed, it is immersed in an electrolytic solution and subjected to an electric current, causing zinc to adhere to the surface. Typical zinc coating thickness: 5–12 μm.
• Pre-galvanizing: The steel strip is galvanized before being rolled and welded into a pipe. Zinc coating thickness: 15–25 μm.
• Hot-dip Galvanizing: After the steel pipe is formed, the entire pipe is immersed in molten zinc at 450°C; a reaction between the zinc and iron creates an alloy layer. Zinc coating thickness: 45–85 μm.

Product Classification

• By galvanizing method: Hot-dip galvanized pipes, cold galvanized (electro-galvanized) pipes.
• By cross-section: Round pipes, elliptical pipes, square pipes.
• By factory form: Straight pipes, pre-bent arch pipes.
• By material: Q195 pipes, Q235B pipes, Q355B pipes.

Features

• Strong resistance to humid heat corrosion: Can withstand long-term high temperature and humidity inside greenhouses, repeated condensation water immersion, and resistance to chemical fertilizers and pesticides, not easy to rust.
• Excellent wind and snow load resistance: High overall strength, can withstand extreme weather impacts such as strong winds and heavy snow, not easy to deform or collapse.
• Easy installation: Lightweight, easy to cut and connect, smooth surface, rapid construction.
• High cost-effectiveness: Service life can reach over 15 years, ready to use without painting, convenient maintenance, low long-term maintenance cost.
• Complete specifications: Full coverage of outer diameter 20–76mm and wall thickness 1.2–3.0mm, all shapes available, meeting different span and load-bearing requirements.

Mechanical Strength / Mechanical Properties

Mechanical Properties Reference (Q195 / Q235B / Q355B)

Material	Yield Strength ReH (MPa)	Tensile Strength Rm (MPa)	Elongation After Fracture A (%)
Q195	≥195	315–430	≥33
Q235B	≥235	370–500	≥26
Q355B	≥355	470–630	≥22

Whole Pipe Load-Bearing Performance (Reference Values)

Outer Diameter × Wall Thickness (mm)	Span (m)	Snow Load (kg/㎡)	Wind Load (m/s)
25×1.5	6	30–40	25
32×2.0	8	40–50	30
42×2.0	10	50–60	33
48×2.5	12	60–80	35

Galvanized Layer Performance

Item	Hot-Dip Galvanizing	Cold Galvanizing
Zinc Layer Thickness	60–300μm	5–15μm
Zinc Coating	80–200g/㎡ double-sided	20–50g/㎡
Salt Spray Test	500–1000 h	100–200 h
Outdoor Lifespan	15–25 years	3–8 years

Applications

• Vegetable cultivation greenhouses: Arch frames, skeletons, and columns of spring-autumn and winter greenhouses, cold greenhouses, multi-span greenhouses, and insect-proof greenhouse supports.
• Livestock and poultry breeding sheds: Main structures of pig sheds, chicken sheds, and aquaculture sheds, suitable for high-humidity and dusty breeding environments.
• Agricultural supporting facilities: Seedling greenhouses, strawberry greenhouses, melon and fruit planting greenhouses, also used for large animal fencing.
• Extended engineering scenarios: Outdoor sunshade canopies, flower house greenhouses, sunlight room frame pipes, agricultural sightseeing greenhouses.

Common Sizes

Outer Diameter (mm)	Wall Thickness (mm)	Common Length (m)	Typical Uses
22	1.2-1.5	6	Arch rods, tie rods
25	1.2-2.0	6	Arch rods, columns
32	1.5-2.0	6	Main arch frames
42	2.0-2.5	6	Load-bearing columns
48	2.0-3.0	6	Large-span main beams
60	2.5-3.5	6	Large multi-span greenhouse frames

Why Choose Us

• Source-integrated factory: Own welded pipe + galvanizing deep processing production lines, no middlemen, stable delivery, capable of undertaking large agricultural engineering projects.
• One-stop customization: Multiple cross-sections, galvanizing processes, and pipe forms available, supporting drawing-based customization of prefabricated components.
• Quality control: Compliant with export standards and quality, raw materials and finished products inspected batch by batch, zinc layer and mechanical properties test reports available.
• Flexible delivery and technical support: Regular stock available, free samples, complete export documents; relying on greenhouse export experience, providing pipe selection solutions.

FAQ

Q: For greenhouse pipes, how do you choose between pre-galvanized, cold-galvanized, and hot-dip galvanized steel?

A: Hot-dip galvanizing offers superior corrosion resistance and is used for long-term greenhouse projects; pre-galvanized steel has a bright finish and is suitable for medium- to long-term projects; cold galvanizing offers high cost-effectiveness and is ideal for simple, short-term structures.

Q: How to choose between square pipes and round pipes?

A: Round pipes have uniform stress distribution and are easy to bend into arches, suitable for arch frames; square pipes are convenient for connection and have good flat surface fit, suitable for columns and crossbeams. Selection can be made according to design drawings.

Q: Why do greenhouse pipes look curved? Can you do pre-bent arch processing?

A: They are generally straight pipes when leaving the factory. The arched pipes we see are generally cold-bent using pipe bending machines. We support pre-bent arch processing and can also do necking processing. Customization with drawings is welcome.