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The globe valve and the gate valve have a certain similarity in appearance, and as both valves have the role of cutting off in the pipeline, so the people always ask what the difference is between the globe valve and the gate valve?
1. The variation in the working principles of globe valve vs gate valve.
Whenever the globe valve opens and closed, the valve stem is lifted, i.e., as the handwheel is rotated, the handwheel rotates and lifts along with the valve stem. The gate valve rotates the handwheel to allow the valve stem to go up and down, and the position of the handwheel does not alter.
The gate valve only has two states that are completely open or completely shut. The opening and closing strokes of the gate is quite wide and the opening and closing time is very long; the movement of the valve plate of the globe valve is much shorter and the valve plate of the globe valve will stop at a certain position during movement. For one, it is used for flow adjustment, while the gate valve can only be used for shut-off and has no other function.
2. The difference in performance the globe valve vs gate valve.
The shut-off valve could be used for cutting and adjusting the flow. The fluid resistance of the globe valve is relatively high, and it is more difficult to open and shut, however since the gap between the valve plate and the sealing surface is small, the opening and closing stroke are small.
The gate valve could only be completely opened and closed. Once completely opened, the flow resistance of the fluid in the valve body path is almost zero, so the opening and closure of the gate valve would be very labour-saving, but the gate is far distant from the sealing surface so, the opening and closing time are large.
3. Installation of the flow difference gate valve vs globe valve.
In both directions, the function of the gate valve is the same. The inlet and outlet directions for installation are not necessary, and the medium could flow in both directions.
The stop valve must be mounted in full compliance with the position suggested by the arrow on the body of the valve. There is also a simple stipulation about the location of the inlet and the exit of the stop valve. China’s “San Hua” valve specifies that the flow path of the stop valve is from top to bottom.
4. The distinction in structure globe valve vs gate valve.
The structure of the gate valve would be more complex than the shut-off valve. From the design point of view, the gate valve is taller than the shut-off valve, and the shut-off valve is longer than the gate valve. In addition, the gate valve is separated into a bright rod and a dark rod.
5. The difference in sealing surfaces:
A small trapezoidal side of the valve core is the screening surface of the valve. Once the core of the valve falls off, it is equivalent to the closing of the valve. The gate valve is sealed on the surface of the valve disc. The sealing effect is not as effective as the globe valve effect.
Summary:
The exterior housing (casing) of the gate and globe valves are identical, except the globe valve is built to act as a control valve, which ensures that it can regulate the flow by the percentage of the opening. The gate valve, however, is not intended to control the flow, but to stop the flow. The door valve should still be either fully open or fully locked.
The major difference is the design of the inner components and the nature of the flow within the valves. In addition, the gate valve can have a rising or not rising stem whereas the globe valve is usually a rising stem configuration. The direction of flow through the gate valve is not necessary. However, the globe valve has a direction of flow marked on the outer casing (body) which indicates the direction of flow from below the seat.