U-shaped steel ring retractable steel arch support
The ring-shaped collapsible stent is also known as a closed collapsible stent. The sections of the stent are connected to form a closed ring, so they are named. The difference between the closed bracket and the arched and trapezoidal bracket is that its bottom is closed, so it brings two outstanding advantages: Because the bracket itself is a closed body, its bearing capacity is greatly improved compared to the arched and trapezoidal bracket. The deformation and damage of the support are small; the bottom of the support is closed, which has a good control effect on the bottom drum of the roadway, and also has a strong control ability on the two sides of the roadway.
The ring-shaped retractable bracket has a complicated structure, a large amount of steel consumption and high cost. Usually, the bracket is used only in the roadway with soft surrounding rock, large mining depth, high pressure, severe bottom drum, and two sides approaching a lot. The main types of ring collapsible brackets are horseshoe, round, square (long) ring, etc.
Trapezoidal retractable metal steel arch support
The trapezoidal retractable metal bracket is generally made of mining I-shaped steel (also made of U-shaped steel). The trapezoidal retractable bracket for mining I-shaped steel is a new type of bracket developed in accordance with China's national conditions and suitable for mining accurate roadways, soft rock roadways and other complicated conditions. Compared with the U-shaped steel retractable bracket, the miner-steel trapezoidal retractable bracket has a simple structure, easy loading and unloading, and low cost. The average cost of steel and support is more than 30%, and the economic benefits are significant.
The trapezoidal retractable stent has a smaller load-bearing capacity than the arched retractable stent, but it does not damage the top plate, can maintain the integrity of the top plate, and has a high cross-section utilization rate. Therefore, under certain conditions, the trapezoidal retractable metal stent also has a wide range of applications and development prospects.
Arched support are widely used in China, especially when the deformation and pressure of the surrounding rock of the roadway is large, using arched brackets has its advantages. The ring-shaped collapsible metal support has a large bearing capacity, can effectively control the bottom drum of the roadway and the movement of the two sides, and is suitable for use in roads with high surrounding rock pressure, especially the pressure of the two sides and the serious bottom drum. When the side pressure and kick drum are not serious, and the roadway pressure and surrounding rock deformation are not too large, a trapezoidal retractable metal bracket can be used.
