Flange type gate valve

The utility model discloses a flange type gate valve which comprises a gate valve pipeline and belongs to the technical field of flange type gate valves, a rotary valve shaft with a rotary disc is installed on the top face of the gate valve pipeline, and an oil pipe is welded to the top face of the output end of the gate valve pipeline. A T-shaped buffering rod piece composed of a piston rod and a piston disc is longitudinally inserted into an inner cavity of the oil pipe, an arc-shaped impact plate is welded to the end, penetrating into the oil pipe, of the piston rod, a top cover is connected to the top end of the oil pipe in a sealed mode, and oil liquid used for buffering impact force is contained between the top cover and the piston disc and located in the oil pipe. The periphery of the gate valve pipeline is sleeved with a U-shaped supporting seat, a mounting base is arranged below the U-shaped supporting seat, and a damping buffering mechanism is mounted between the mounting base and the U-shaped suppo