09,22,2026 17 views
The difference between globe valve and gate valve
1. Different structures
Gate valves have a more complex structure and larger height dimensions compared to globe valves. From an external perspective, gate valves are shorter and taller than globe valves, especially rising stem gate valves that require higher height space. This should be noted when selecting a valve with limited installation space.
2. Different sealing surfaces
During the opening and closing of gate valves, the sealing surfaces of the valve core and seat are always in contact and rub against each other, making the sealing surfaces prone to wear. Especially when the valve is in a near closed state, the pressure difference between the front and rear of the valve core is large, and the wear of the sealing surface is even more severe;
Once the valve disc of the globe valve is in the open position, there is no longer contact between its valve seat and the sealing surface of the valve disc, so its sealing surface has less mechanical wear. However, if the medium contains solid particles, it is easy to damage the sealing surface.
The sealing surface of a gate valve has a certain degree of self sealing ability, and its valve core tightly contacts the sealing surface of the valve seat by the medium pressure, achieving a tight and leak free seal. The inclination of the valve core of a wedge gate valve is generally 3-6 degrees, and the valve core is prone to jamming when forced to close excessively or when the temperature changes significantly. So, high-temperature and high-pressure wedge gate valves have taken certain measures to prevent the valve core from getting stuck in the structure.
The sealing surface of a globe valve must be forcibly closed to achieve sealing. Under the same diameter, working pressure, and driving device, the driving torque of a globe valve is 2.5 to 3.5 times that of a gate valve. This should be taken into account when adjusting the torque control mechanism of electric valves.
The sealing surface of the globe valve only comes into contact with each other when it is closed, and the relative slip between the forcibly 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 caused by impurities in front of the valve core and sealing surface, or by the lack of tightness in the closed state, resulting in high-speed flushing of the medium.
3. Different flow resistance
When the gate valve is fully opened, the entire flow channel is straight through, and the pressure loss of the medium during operation is minimized. Compared with globe valves, its main advantage is that the fluid flow resistance is small. The flow resistance coefficient of ordinary gate valves is about 0.08~0.12, while that of ordinary globe valves is about 3.5~4.5. The opening and closing force is small. Gate valves are usually suitable for operating conditions where frequent opening and closing is not required, and the gate is kept fully open or closed. They are not suitable for regulating or throttling purposes. The flow resistance and unbalanced force of the globe valve are large throughout the entire stroke, and the required driving force or torque is correspondingly much larger. But it is very suitable for regulating and throttling fluids.
For high-speed flowing media, when the gate is partially opened, it can cause valve vibration, which may damage the sealing surfaces of the gate and valve seat. Throttling can cause the gate to be eroded by the medium.
4. Flow direction is different
When installing a globe valve, the medium can enter from below the valve core or from above. The advantage of the medium entering from below the valve core is that when the valve is closed, the packing is not under pressure, which can extend the service life of the packing and allow for replacement of the packing when the pipeline in front of the valve is under pressure. The disadvantage of medium entering from below the valve core is that the driving torque of the valve is relatively large, about 1.05-1.08 times that of entering from above, and the axial force on the valve stem is large, making the valve stem prone to bending. For this reason, the method of medium entering from below is generally only suitable for small caliber globe valves (below DN50), while globe valves above DN200 use the method of medium entering from above. Electric globe valves generally use the method of medium entering from above. The disadvantage of entering the medium from above is exactly the opposite of entering from below. The flow direction of the gate valve has the same effect when entering from both sides.
Compared with gate valves, globe valves have the advantages of simple structure, good sealing performance, and easy manufacturing and maintenance; The disadvantage is that the liquid resistance is high, and the opening and closing force is large.
5. Different itineraries
The stroke of a gate valve is larger than that of a globe valve.
6. Different maintenance processes
The maintenance of gate valves is not suitable for on-site pipelines, while the valve seats and discs of most globe valves can be replaced online without removing the entire valve from the pipeline. This is very suitable for situations where valves and pipelines are welded together.
The purpose of globe valves and gate valves
1. The purpose of globe valve
Globe valves can be used in most medium process systems. We have developed various forms of globe valves that meet the needs of various departments such as petrochemicals, electricity, metallurgy, urban construction, and chemical engineering.
The use of globe valves is extremely common, but due to the large opening and closing torque and long structural length, the nominal diameter is usually limited to 250mm or less, and there are also some up to 400mm. However, special attention should be paid to the inlet and outlet directions when selecting. Generally, the medium of globe valves below 150mm mostly flows in from below the valve disc, while the medium of globe valves above 200mm mostly flows in from above the valve disc. This is due to the consideration of the closing torque of the valve. In order to reduce the opening or closing torque, globe valves above 200mm are generally equipped with internal or external bypass valves.
2. The purpose of gate valve
Gate valves are only used for fully opening and fully closing various pipelines or equipment for the operation of media, and are not allowed to be used for throttling.
Gate valves with handwheels or handles should not be operated with additional auxiliary bars (if the seal is not tight, the sealing surface and other parts should be inspected and repaired). Rotate the handwheel and handle clockwise to close, and vice versa to open. Gate valves with transmission mechanisms should be used according to the instructions in the product manual.
In summary, there are many differences and uses between gate valves and globe valves. In our selection and use, we must distinguish their similarities and differences well in order to avoid mistakes. The application range of gate valves and globe valves is determined by their characteristics. Generally, in smaller channels, globe valves are usually used when good shut-off sealing is required. In steam pipelines and large-diameter water supply pipelines, gate valves are commonly used due to the requirement for low fluid resistance.
