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Gate valves and globe valves are shut-off valves and are the two most common types of valves.

From the perspective of appearance, the gate valve is shorter and taller than the globe valve, especially the open stem valve needs a higher height space. The sealing surface of the gate valve has a certain self-sealing ability, and its valve core is tightly contacted with the sealing surface of the valve seat by the pressure of the medium, so as to be tight and leakproof. The spool slope of the wedge gate valve is generally 3 ~ 6 degrees. When the valve is forced to close excessively or the temperature changes greatly, the spool is easy to get stuck. Therefore, high-temperature, high-pressure wedge gate valves have taken certain measures to prevent the valve core from jamming. When the gate valve is opened and closed, the sealing surface of the valve core and the seat is always in contact and rubs against each other, so the sealing surface is easy to wear, especially when the valve is close to the closed state, the pressure difference between the front and back of the valve core is large, and the sealing surface wear is more serious .

Compared with gate valves, the main advantage of gate valves is that the resistance of fluid flow is small. The resistance coefficient of common gate valves is about 0.08 ~ 0.12, while the resistance coefficient of ordinary gate valves is about 3.5 ~ 4.5. The opening and closing force is small, and the medium can flow in two directions. The disadvantage is that the structure is complex, the height and size are large, and the sealing surface is easy to wear. The sealing surface of the shut-off valve must be forced to close the valve to achieve the seal. Under the same caliber, working pressure and the same driving device, the driving torque of the shut-off valve is 2.5 to 3.5 times that of the gate valve. This should be paid attention to when adjusting the torque control mechanism of the electric valve.

The sealing surfaces of the shut-off valve only contact each other when they are completely closed. The relative sliding amount of the force-closed valve core and the sealing surface is very small, so the wear of the sealing surface is also very small. The wear of the sealing surface of the globe valve is mostly due to the presence of debris before the valve core and the sealing surface, or due to the lack of tightness in the closed state, which causes high-speed erosion of the medium.

When the globe valve is installed, the medium can enter from the bottom of the spool and from the top. The advantage of the medium entering from below the spool is that the packing is not under pressure when the valve is closed, which can extend the service life of the packing and can be used to replace the packing under the condition that the pipeline in front of the valve is under pressure. The disadvantage of the medium entering from below the valve core is that the driving torque of the valve is relatively large, which is about 1.05 ~ 1.08 times of entering above. The axial force on the valve stem is large, and the valve stem is easy to bend. For this reason, the medium entering method from below is generally only suitable for small-diameter manual cut-off valves, and the limit is that the force of the medium acting on the valve core when the valve is closed is not more than 350kg. The electric shut-off valve generally adopts the way that the medium enters from above. The shortcomings of the medium entering from above are just opposite to the way of entering from below.

Compared with gate valve, globe valve has the advantages of simple structure, good sealing performance, and convenient manufacturing and maintenance; the disadvantage is that the liquid resistance is large, and the opening and closing forces are large. Gate valves and globe valves are fully open and closed valves. They are used to cut off or connect media, and should not be used as regulating valves.

The application range of globe valves and gate valves is determined according to their characteristics. In smaller channels, when better shut-off tightness is required, stop valves are mostly used; in steam pipes and large-diameter water supply pipes, gate valves are generally used because fluid resistance is generally required to be small.