U-shaped steel arch support (full name: hot-rolled U-shaped steel for mine roadway support) U-shaped steel is a kind of steel with a cross-section like the English letter "U", and sometimes the cross-section is in the shape of the Japanese letter "ひ".
The main features of U-shaped steel arch support: high pressure, long support time, easy installation and not easy to deform. Main uses: Mainly used for mine tunnels, secondary support of mine tunnels, and support and support of mountain tunnels.
The use of U-shaped underground roof support effectively reduces the occurrence of roof fall, slabs and other accidents, is safe and reliable, and improves the stability of the mine ventilation system. The use of U-shaped steel retractable support can better solve the problem of tunneling and support. As the main section steel for manufacturing roadway shrinkable tunnel roof support, U-section steel is widely used at home and abroad.
However, due to the inconsistent understanding of the performance and requirements of U-shaped tunnel roof support itself, the cross-sectional shape, geometric parameters and material of U-shaped steel vary from country to country. There are mainly four types of U-shaped underground roof support produced in my country: 18U, 25U, 29U, and 36U. The first two are products from the 1960s, which belong to waist positioning; the latter two are products from the 1980s, which belong to ear positioning.
Due to its low carrying capacity, U18 is rarely produced. In addition to the above four types of U-shaped underground roof support in GB/T 4697-2008, a new type of 40U is added. The unit weight of each model of U-shaped steel is as follows: 18UY 18.96 kg/m25UY 24.76 kg/m25U 24.95 kg/m29U 29 kg/m36U 35.87 kg/m40U 40.05 kg/m. The "Y" after the model indicates waist positioning.
