Valve regulates flow

The gate valve can only be used as a shut-off valve and cannot regulate flow.

Gate valves and parallel gate valves. The function of this type of valve is to only allow the medium to flow in one direction and prevent the flow in one direction. Usually this kind of valve works automatically. Under the pressure of fluid flowing in one direction, the valve disc opens; when the fluid flows in the opposite direction, the fluid pressure and the self-weight of the valve disc act on the valve seat, thus cutting off the flow. ...

I strongly agree with the second floor's opinion. The gate valve should only have two states: open and closed. It is a mistake for some units to use gate valves to control flow. This will cause great damage to the gate valve. However, gate valves are relatively cheap, and their opening can also be used to adjust pressure and flow. Usually used as a bypass valve for regulating valves.

The gate valve is only used for opening and closing, without throttling. If the gate valve is not fully opened, it will easily produce vibration, which is not good for the valve itself and the pipeline!

Very :handshake agree :)

Globe valves, butterfly valves and needle valves regulate flow, but from the perspective of most companies, gate valves are still used. Reply: There are descriptions of valves in chemical engineering manuals. According to my personal point of view, firstly, the choice of valve type should also consider the convenience of opening. For valves that are too large (DN200 and above), the convenience of workers' operation should be considered. The second is to consider the nature of the medium. For example, it is recommended to use a stop valve for vacuum and compressed air. ； For water quality, it is recommended to use ball valves, gate valves, and butterfly valves (butterfly valves are generally used in main valves or large root valves) ； Fluids with high viscosity generally use ball valves or gate valves (depending on the specific situation); for steam, it is recommended to use plunger valves and stop valves. ； If it is a highly toxic and harmful substance, special considerations must be taken. In short, it is recommended to consider many aspects when selecting a valve, and the design must be meticulous.

Structurally speaking, using a gate valve to control flow can easily cause the gate plate to be damaged and fall off.

Continuing with the topic of my friend upstairs, gate valves and ball valves adjust the flow rate through the opening angle of the valve core gate plate and the valve core ball. The maximum opening of the valve core is 90 degrees, which is the maximum flow of the valve. The stop valve adjusts the opening degree of the valve by rotating the valve stem to drive the lifting movement of the valve core. Please consider whether the stroke of the valve stem or the angle of the gate plate is easier to control, or which one is relatively more accurate.

Haha, it all makes sense.

It is not advisable to use a gate valve to adjust the flow. The valve core is easily damaged. Use a regulating valve to adjust the flow.

Both can be closed, and flow adjustment can be performed in situations where flow linearity is not required. It's just that the stop valve has large flow resistance due to its structural characteristics, so gate valves are more commonly used where throttling is required. In addition, whether the stop valve is installed forward or backward, there is always a very laborious opening and closing process, so it cannot be made very large, otherwise it will be difficult to open and close. In addition, the stop valve has the characteristics of good one-way sealing effect, so it is also useful in situations where the reverse flow of working fluid is prevented. If the above factors are not considered, both can be used interchangeably. (2) Gate valve refers to a valve in which the closing member (gate plate) moves in the vertical direction along the center line of the passage. Gate valves are mainly used for cutting off in pipelines. Gate valve is a widely used valve. Generally, it is used for cutting devices with a diameter of DN≥50mm. Sometimes, gate valves are also used for cutting devices with very small diameter. Gate valves have the following advantages.: ①Fluid resistance is small. ②The external force required for opening and closing is small. ③The flow of media is unrestricted. ④When fully open, the sealing surface is less eroded by the working medium than the stop valve. ⑤The body shape is relatively simple and the casting process is good. Gate valves also have shortcomings: ①The overall dimensions and opening height are both large. The installation requires a large space. ②During the opening and closing process, there is relative friction between the sealing surfaces, which can easily cause scratches. ③Gate valves generally have two sealing surfaces, which adds some difficulties to processing, grinding and maintenance.

The gate valve has small flow resistance and requires laborious opening and closing. It is widely used for opening and closing of various medium pipelines. When the valve is partially opened, eddy currents are generated on the back of the gate, which can easily cause corrosion and vibration of the gate, and can easily damage the sealing surface of the valve seat, making repair difficult. Therefore, gate valves are generally not used for throttling.