Flapper valve is usually installed in the middle of the silo and unloader, usually when enabled, are present in unloader fails, or needs maintenance, truncated material usage. After removing the discharger prevent dust silo leak causing dust pollution. In order to ensure the reliability of the flapper valve at work, in the installation and routine maintenance has a lot of precautions, we explain below. Installation and maintenance of the flapper valve should note the following: hand wheel, handle and drive mechanism for lifting are not allowed to use, and forbid the collision. Flapper valve should be mounted vertically (ie stem in a vertical position, the hand wheel at the top). Flapper valve with a bypass valve opens the bypass valve opening should be preceded (in order to balance imports and exports and reduce the pressure opening force). With a flapper valve drive mechanism, according to the provisions of product installation instructions. If the flapper valve switch is used frequently, lubrication at least once a month. Flapper valve is used as the cut-off media use, in the full flow through the pressure medium to run minimal loss at this time. Flapper valve normally does not require frequent opening and closing, and keeping the shutter fully open or fully closed condition. Not available for use as a regulator or throttling. For the high-speed flow of medium, open the gate in local conditions can cause vibration of the gate, while the vibration it may damage the gate and seat sealing surface, and the throttling damper will suffer erosion of the medium. My company has a professional R & D talent and technology specialist, has rich material and human resources. Companies with customer site requirements using computer-aided drafting, and whom the selection based on customer needs, providing effective design solutions to meet customer requirements.