U channel bar 

U channel bar is a steel English like the letter "U" with a cross section, sometimes with a cross section of Japanese letters "better" shape.

The latest standard, issued in 2008, was introduced in April 1, 2009 and recommended by the national standards

GB/T 4697-2008

U channel bar bracket

Main features: large pressure, long support time, easy installation, not easy to deformation and so on.

Main uses: mainly used in mine roadway, roadway support, and two times of the tunnel supporting etc..

As the main shape steel for the retractable metal support of tunnel, U channel bar is widely used at home and abroad.

However, because of the inconsistent understanding of the properties and requirements of U channel bar, the shape, geometrical parameters and material of U channel bar are different from each other.

There are four types of U channel bar produced in our country, 18U, 25U, 29U and 36U. Among them, the first two kinds of 60s products, belong to the waist positioning; the latter two are 80s products, is the ear positioning. U18 is rarely produced because of its low carrying capacity.

In the GB/T 4697-2008, in addition to the above four models of U steel, the new 40U model.

The single weight of each model U is as follows:

18UY 18.96, kg/m

25UY 24.76, kg/m

25U 24.95, kg/m

29U 29, kg/m

36U 35.87, kg/m

40U 40.05, kg/m

Among them, the model with "Y" means waist positioning.

U steel varieties Name: cold-formed U steel, large size U channel bar, automobile special U channel bar, hot galvanized, U channel bar and other open cold-formed steel.