Abstract: Taking practice of gas extraction and sealing hole grouting in coal mine as background, a new type of blast valve was developed in view of the current situation that the existing blast valves can not meet the requirements of new grouting sealing device. It interprets the failure mechanism of the blast disc and optimizes the key parameters of the new blast valve through laboratory tests. The fixed blast has the function of constant value opening, and can effectively prevent the slurry backflow. Through finite element approach analysis, it is found that the blast disc is usually damaged at the fixed edge, and the greater the height diameter ratio, the more obvious the damage is. This shows that with the deformation of the blast disc, the blast disc tends to be more and more damage. Laboratory tests show that the bursting pressure decreases with the increase of gasket diameter, meanwhile, it increases with the increase of aluminum foil thickness. In addition, the Kb value of three different thickness aluminum foil are not the same, but increases with the increase of aluminum foil thickness.