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Mine Door Pneumatic Control Devices is a mine ventilation control device developed based on pneumatic transmission technology. It uses compressed air from the mine as the power source and achieves automatic opening and closing of the air door through pure pneumatic or electric pneumatic hybrid control mode.
link:https://www.rlycn.com/mining-ventilation-system/mine-door-control-devices/mine-door-pneumatic-control-devices.html
Mine Door Pneumatic Control Devices