,Application:
It is used for coal water injection, dust falling, coal pressure reduction, coal cracking, gas drainage, etc.
2,Function:
1 By injecting water into coal mass, some of the gas can be discharged, thus the gas content of the coal mass can be effectively reduced.
2 If water injection achieves the desired effect, the dust can be redued by more than 80%, thus improving the working environment and avoiding dust explosion accident. 
3 It can dampen the coal and prevent spontaneous combustion of coal.
4 It uses high pressure water injection to break the coal mass, so as to reduce fire work products, reduce the cost and improve the security of workers.
5 It breaks the coal with hole sealing device, thus effectively preventing coal and gas outburst and explosion.
3,Structure:
The hole sealing device is composed of high pressure rubber expansion hose, relief valve, and quick connector.
4,Technical Papramenters:
Sealing diameter: 30-120mm (can be processed according to customer’s requirements)
Working pressure: 1-8Mpa(can be processed according to customer’s requirements)
Start-up pressure of relief valve: 0. 4-0. 5Mpa  
Working flow: water injection 4t-4.5t/h
Sealing depth:1m-8m
Hose expansion coefficient: 60%-100%
5,Operation Guides and Precautions:
1 The coal seam water injection hole sealing device is easy to use. You only need to connect the hole sealing device to the waterway on the working site and fully insert the hole sealing device into the borehole. Under certain pressure, the hole sealing device hose expands to realize hole sealing and water broken blasting.
2 The coal seam water injection hole sealing device can be used repeatedly for serveral times. After water injection, remove the pressure, and the hoel sealing device can get back into shape, then you can take the devie out.
3 It is forbidden to insert and take out the device with pressure.
4 Please ensure nobody is working in front of the hole sealing device when it is operating.