Flat Bar Rails

Flat bar rails and square bar rails are two common types of solid steel bars. Flat bars have a rectangular cross-section, while square bars have a square cross-section—hence the names. Their specifications are typically expressed in terms of width × thickness. For example, a 40×30mm flat bar means it is 40 mm wide and 30 mm thick. These steel bars have a wide range of uses: they can be directly used as crane rails or serve as raw materials for further processing. Common materials include Q235, Q355, and #45 steel.

Flat Bar Rail Key Features

Simple Cross-Section

Unlike standard rail profiles, flat bar rails have a rectangular cross-section, while square bars are square-shaped. This geometry allows for easy installation and maintenance, especially in flexible track layouts.

Weldable Connection

Flat and square bar rails do not require fishplates for joining. Instead, they can be directly welded using standard welding rods, offering a more seamless and efficient installation process.

Flat Bar Rail Type

Size	Height (mm)	Width (mm)	Weight (kg/m)
Size	X	Y	Weight (kg/m)
40x30mm	30	40	9.42
50x30mm	30	50	11.775
60x40mm	40	60	18.84
65x40mm	40	65	20.41
70x40mm	40	70	21.98
75x40mm	40	75	23.55
80x60mm	60	80	37.68
90x40mm	40	90	28.26
100x60mm	60	100	47.1

Square Bar Rail Type

Size	Height (mm)	Width (mm)	Weight (kg/m)
Size	X	Y	Weight (kg/m)
30x30mm	30	30	7.065
40x40mm	40	40	12.56
50x50mm	50	50	19.625
60x60mm	60	60	28.26
70x70mm	70	70	38.465
80x80mm	80	80	50.24
90x90mm	90	90	63.585
100x100mm	100	100	78.5
110x110mm	110	110	94.985

Flat Bar Rails Applications

Crane Tracks: Available in various sizes tailored to match light-duty crane wheels.

Precision Parts: Cold-drawn flat bars serve as high-quality raw materials for manufacturing precision components.

Construction: Commonly used in structural components such as support columns and steel beams.

Machinery: Suitable for shafts, die blanks, and mechanical parts.

Decorative Engineering: Square bars are often used for framing doors and windows, stair railings, and other decorative metalwork.

Manufacturing Processes

There are three common manufacturing methods for flat bars: hot rolling, cold rolling, and cold drawing.

Hot rolling: This process involves heating steel billets to a high temperature and then rolling them into flat bars. It requires high temperatures during processing and offers fast forming speed.

Cold rolling: This method forms flat bars by rolling hot-rolled steel at room temperature on a cold rolling mill. It helps reduce the thickness of the steel bar and improves surface quality.

Cold drawing: This process involves drawing square or round steel into flat bars at room temperature. It does not generate heat during processing and maintains high dimensional accuracy and surface finish.

Hot-Rolled vs Cold-Rolled vs Cold-Drawn Flat Bar Rails: Visual Differences?

Process Type	Surface Appearance	Dimensional Accuracy	Cross-Section Shape
Hot-Rolled	Rough surface with mill scale; dark gray or reddish tone; visible pitting and bumps	Low; noticeable variations in width and thickness; irregular edges	Irregular; corners are rounded or beveled
Cold-Rolled	Smooth and flat surface; uniform silver-gray color with metallic sheen	Higher; more consistent width and thickness; slightly rounded edges	Relatively regular; corners are smooth
Cold-Drawn	Bright silver surface with the highest gloss and cleanliness	Highest; minimal size deviation, difficult to detect by eye; sharp edges	Most regular; nearly right-angled corners and excellent straightness

Looking for flat bar rails for cranes, mining carts?

We provide flat bar rails in various widths, thicknesses, and finishes.

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