Stainless Steel Square Tube

Specification

Item	Stainless Steel Square Pipe
Material & Grade	201, 301, 301L, 304, 304L, 304N, 316, 316L, S30815, 409, 430
Production Type	Welded (ERW, SSAW, LSAW), Seamless
Thickness	0.6mm – 5.0mm
Length	0.5-6.0M
Surface Finish	2B, BA, Polished, Satin Finish (180grit, 320grit), Mirror Finish
Standard	ASTM, JIS, DIN, GB
Certificates	ISO, AEO, MTC
Processing Service	Welding, Cutting, Bending, Decoiling, Punching
MOQ	10 Tons
Delivery Time	15-21 Days
Packaging	Seaworthy packing

Common surface treatments

• NO.1: Also known as 1D, rough and matte, grayish-white in color, with obvious rolling marks on the surface, low cost.

• 2D: Silvery-white matte, smoother than NO.1, but without obvious gloss, soft material, suitable for deep drawing.

• 2B: The most cost-effective general-purpose surface, medium gloss, matte finish, does not reflect images, balances workability and appearance.

• No.3: Coarse continuous straight lines, with a certain gloss, polished and rolled from 2D or 2B sheets.

• HL/No.4: Also known as fine sandblasted surface, fine and uniform short filament texture, slightly glossy, commonly known as “short filament brushed finish,” with better fingerprint resistance than mirror finish.

• HL: Hairline finish, continuous, highly directional brushed effect, more decorative, longer and more coherent straight lines. HL has a greater sense of visual extension than NO.4, often used in modern style designs.

• BA: Bright Annealed, high reflectivity, near-mirror finish, smooth and oxidation-free surface, superior reflectivity to 2B. BA is not the final polished surface, but can be used as a pre-processing step for 8K.

• No. 8 / 8K: Extremely high gloss, clearly reflects portraits, similar to a glass mirror. 6K: Slight pitting, blurry image. 8K: Flawless, clear image. Finely polished 8K: Gloss comparable to glass. Prone to fingerprints and scratches, requires an anti-fingerprint coating.

Classification of stainless steel square tubes

Classified By Material

1. 304 Stainless Steel Square Tube: The most widely used grade, standard grade is 0Cr19Ni9, also known as “18/8 stainless steel”. Excellent corrosion resistance and formability.
2. 304L Stainless Steel Square Tube: Belongs to ultra-low carbon stainless steel, with superior weldability and less susceptibility to intergranular corrosion after welding.
3. 316 and 316L Stainless Steel Square Tubes: Contain molybdenum, offering stronger resistance to salt water and corrosion, ideal for marine and industrial environments, with superior high-temperature resistance and creep resistance.
4. 201 Stainless Steel Square Tube: Low-nickel stainless steel tube. An economical alternative to 304, suitable for decorative and low-corrosion applications. Relatively inexpensive.
5. 2205 Duplex Stainless Steel Square Tube: Combines the advantages of austenitic and ferritic stainless steels, with a pitting equivalent (PREN) value of over 35, strong corrosion resistance, and significant advantages in marine and chemical environments.

Classification By Process

1. Stainless steel welded square tube: Made from stainless steel strip as the base material, it is formed into a round tube through unpacking, flattening, rolling, and welding, and then rolled into a square tube. The cost is relatively low.
2. Stainless steel seamless square tube: Made from seamless SS round tubes through hot rolling, piercing, cold rolling, or extrusion. It has no welded joints and is suitable for high-pressure and high-strength applications.

Performance advantages

Highly corrosion-resistant

The surface has a passivation film, requiring infrequent maintenance; its use is not limited by the environment; it can withstand acid and alkaline fluids for a long time; and it offers excellent cost performance. It is the preferred choice for marine vessels and industrial environments.

Exceptional strength and durability

Thanks to its square cross-section, SS square tubes weigh only one-third of traditional carbon steel tubes while maintaining the same bending and torsional strength. Our square tubes can withstand heavy loads, extreme temperatures, and mechanical stresses without deformation or failure.

Good plasticity

It is easy to cut, bend, weld, and stamp, and can easily handle complex parts and decorative construction scenarios. The right-angle design and precise dimensions provide great convenience for installation and construction.

Aesthetically pleasing and easy to clean

Our stainless steel square tubes can be polished, brushed, mirror-finished, and other surface treatments, presenting different luster and texture. The smooth surface does not easily accumulate dust and dirt, making it suitable for the food and medical fields. These are characteristics of stainless steel tubes.

Common Applications

Architectural Decoration

Used as structural support in high-rise buildings, or as the frame for curtain walls, door and window frames, and as stair railings, partitions, display shelves, and artistic designs in residences, shopping malls, and subway stations.

Machinery and Industry

Used for machine frames, guide rails, and supports in automated production lines. Also used for steel pipes in high-temperature boilers, pressure vessels, and hydraulic supports. High-temperature, high-pressure pipelines are used in nuclear power and chemical projects.

Food and pharmaceutical industries, transportation

Fermentation tanks, cleanroom equipment, reaction vessels, and piping; automobile frames, exhaust pipes, bumpers, luggage racks, and structural components; internal supports for high-speed railways and subways; and ship deck railings.

Public facilities

Bus stop canopies, bicycle racks, green belt fences, road guardrails, airport terminals, and outdoor billboards; bed frames, table legs, display case frames, hospital beds, trolleys, operating table supports, fitness equipment, lighting fixtures, and household appliance housings.

304/316 stainless steel square pipe weight chart

Size (mm)	1.0mm	1.2mm	1.5mm	2.0mm	2.5mm	3.0mm	4.0mm
20×20	0.60	0.757	0.942	1.25	1.55	1.85	—
25×25	0.789	0.946	1.180	1.568	1.950	2.326	—
30×30	0.946	1.138	1.423	1.892	2.355	2.812	—
40×40	1.26	1.51	1.89	2.52	3.14	3.58	4.74
50×50	1.58	1.89	2.37	3.15	3.92	4.68	6.18
60×60	1.89	2.27	2.85	3.79	4.72	5.64	7.43
80×80	2.52	3.03	3.79	5.04	6.28	7.51	9.98
100×100	3.15	3.79	4.74	6.29	7.84	9.38	12.48

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Glory Steel Plant, 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 pipes, stainless steel pipes, and alloy steel pipes. With our high-quality products and services, we export to over 120 countries.