Once the shut-off valve is in the open state, there is no contact between its seat and the sealing surface of the disc, so its sealing surface is less mechanically worn, because most of the valve seats and discs are easier to repair or replace There is no need to remove the entire valve from the pipeline when sealing the components, which is very suitable for the occasion where the valve and the pipeline are welded together. The flow direction of the medium through this type of valve has changed, so the flow resistance of the stop valve is higher than that of other valves.

Features

(1) The structure is simpler than gate valve, and it is more convenient to manufacture and maintain.

(2) The sealing surface is not easy to wear and scratch, and the sealing performance is good. There is no relative sliding between the valve disc and the sealing surface of the valve body when opening and closing, so the wear and scratches are not serious, the sealing performance is good, and the service life is long.

(3) When opening and closing, the disc stroke is small, so the height of the stop valve is smaller than the gate valve, but the structure length is longer than the gate valve.

(4) The opening and closing moment is large, the opening and closing is more laborious, the headmaster of the opening and closing time.

(5) The fluid resistance is large, because the medium channel in the valve body is tortuous, the fluid resistance is large, and the power consumption is large.

(6) When the nominal pressure of the medium flow direction is PN≤16MPa, the downstream flow is generally adopted, and the medium flows upward from below the valve flap; when the nominal pressure PN≥20MPa, the reverse flow is generally adopted, and the medium flows downward from the top of the valve flap to increase the sealing capacity. . When in use, the stop valve medium can only flow in one direction, and cannot change the flow direction.

(7) The valve disc is often eroded when fully opened. The stem axis of the globe valve is perpendicular to the sealing surface of the valve seat. The opening or closing stroke of the valve stem is relatively short, and it has a good cut-off action, making this valve very suitable for cutting or regulating and throttling of the medium. Once the valve disc of the manual shut-off valve is in an open condition, there is no longer contact between its valve seat and the sealing surface of the disc, and it has a reliable cut-off action. This kind of valve is very suitable for cutting or adjusting and reducing the medium. Stream usage.