Abstract: The device for blocking gangue between hydralic supports is the important guarantee to avoid the situation that coal and gangue slide down to hurt people and destroy equipment, when assigning fully-mechanized longwall face on the strike with true-inclined or false-inclined layout in the steeply inclined coal seam. In this paper, based on assive investigation and plan comparison, a light-weight device for blocking gangue with metal net and four-door combination has been developed. The device increases the adaptability to the changes of dip angle and mining height of coal seam, and can change the advance directions of working face, by using the sliding system of ball bearing type, symmetric design and changeable size of doorframe. The numerical simulation results show that the device can meet the needs to prevent coal and gangue, the sliding system composed of guide rails, rollers and limit rails presents high flexibility, and can avoid the problem that the device for blocking gangue may fail to work under hydraulic control, after adoting manual control to close sliding door. In addition, when using metal-net frame structure in the hanging door and sliding door, can reduce the local ventilation resistance of working face, and is helpful to the ventilation stability of working face. Field tests indicate that the weight of light-weight device for blocking gangue between supports is reduced two thirds of that of the previous planer device for blocking gangue, and it is convenient to transport, install and maintain．

Key words: mining engineering；longwall mining；between hydraullic supports；device for blocking gangue, metal net