Black Rectangular Steel Tube

Black Rectangular Steel Tube: The Robust Backbone for Modern Fabrication

For industrial builders, architectural fabricators, and DIY enthusiasts seeking a combination of exceptional strength, clean aesthetics, and versatile form, the black rectangular steel tube is an indispensable material. Unlike standard hot-rolled sections, our black rectangular steel tubes offer a superior finish and dimensional consistency, making them ideal for projects where both structural integrity and visual appeal are paramount. This product is part of our comprehensive range of structural hollow sections, which includes options like the Striped Rectangular Hollow Section for specialized grip applications, the uniformly coated Black Finished Rectangular Tube, and the robust Black Rectangular Pipe. For those requiring a textured surface for enhanced adhesion or a unique look, our Striped Rectangular Steel Pipe provides an excellent alternative. The defining characteristic of the black rectangular steel tube is its mill finish—a dark, scale-rich surface formed during the manufacturing process that provides a natural protective layer against corrosion in certain environments and offers an industrial, ready-to-use appearance perfect for modern designs.

Detailed Specifications and Technical Data

To ensure your project specifications are met with precision, our Black Rectangular Steel Tube is manufactured to exacting standards. The product is typically made from structural steel grades such as ASTM A500 Grade B or C, ensuring high yield and tensile strength. The tubes are formed through a continuous weld process, creating a consistent and reliable seam. Below are the key parameters available in our standard inventory. Custom sizes and chemistries can be accommodated for large-scale orders.

Commonly Available Sizes (Outer Dimensions & Wall Thickness):

• 1" x 2" (25mm x 50mm) - Wall: 16ga (1.5mm), 14ga (2.0mm), 1/8" (3.2mm)
• 2" x 2" (50mm x 50mm) - Wall: 14ga (2.0mm), 1/8" (3.2mm), 3/16" (4.8mm)
• 2" x 3" (50mm x 75mm) - Wall: 14ga (2.0mm), 1/8" (3.2mm), 3/16" (4.8mm)
• 2" x 4" (50mm x 100mm) - Wall: 1/8" (3.2mm), 3/16" (4.8mm), 1/4" (6.4mm)
• 3" x 4" (75mm x 100mm) - Wall: 1/8" (3.2mm), 3/16" (4.8mm), 1/4" (6.4mm)

Material and Mechanical Properties Table:

Standard Lengths and Tolerances:

The Black Rectangular Steel Tube is supplied in random mill lengths, typically ranging from 18 to 24 feet (5.5 to 7.3 meters). Custom cut lengths are available. Standard tolerances comply with ASTM A500 for outside dimensions, wall thickness, and straightness.

• Outside Dimensions Tolerance: ±0.020 inches for sizes under 3 inches, ±0.5% for sizes 3 inches and over.
• Wall Thickness Tolerance: ±10% of the nominal wall.
• Straightness: Maximum deviation of 1/8 inch per 10 feet of length.

The inherent strength-to-weight ratio of the Black Rectangular Steel Tube makes it a top choice for frameworks, supports, gates, fencing, handrails, and machinery bases. Its flat surfaces simplify fabrication, welding, and joining compared to round tubing. When specifying, consider the environment; while the mill scale offers some protection, for exterior applications or corrosive atmospheres, priming and painting or powder coating are recommended for long-term durability.