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Heavy duty cold bending U series

U steel is a kind of like the English letter "U" cross section of the iron and steel, sometimes cross section in the shape of Japanese letters "??".

Main features: high pressure, long support time, easy to install and not easy to deform.

Main USES: mainly used for mine roadway, secondary support of mine roadway, and support of tunnel through mountain, etc.

U-shaped steel is widely used at home and abroad as the main shape steel for manufacturing yielding metal support of roadway.

However, due to the inconsistent understanding of the properties and requirements of u-shaped steel itself, the section shape, geometric parameters and materials of u-shaped steel vary from country to country.

There are four types of u-shaped steels in China: 18U, 25U, 29U and 36U. Among them, the first two are products of the 1960s, which belong to the waist positioning; The latter two are products of the 1980s, which are ear-oriented. Because the bearing capacity of U18 is very low, it is seldom produced now.