I would like to ask in what situations gate valves, ball valves, and butterfly valves are used?

There are also globe valves, plug valves, diaphragm valves, safety valves, control valves, check valves, pressure reducing valves, and so on. The following are some simple guidelines for selecting valves for reference: 1. When the pipe diameter is 50 mm or less, globe valves or ball valves are suitable. 2. In areas with limited installation space, butterfly valves or ball valves are preferable; if a gate valve must be used, a hidden stem type should be chosen. 3. In areas where low flow resistance is required (such as on the suction pipe of a water pump), gate valves or butterfly valves are appropriate. 4. Gate valves, ball valves, and butterfly valves should be used on pipe sections that require two-way flow; globe valves should not be used. 5. Throttle valves and globe valves are suitable for adjusting flow rate and pressure. 6. Globe valves are appropriate for components that need to be opened and closed frequently. 7. Globe valves can be used when the medium is clean; gate valves, ball valves, butterfly valves, or plug valves are better suited when the medium contains suspended particles or is viscous. 8. Globe valves and gate valves are suitable for steam pipelines, while butterfly valves and gate valves are suitable for water pipelines

The selection of a valve depends on both the characteristics of the valve itself and the conditions of the fluid it handles. 1. Gate valves have a gate-shaped closing element, and since the direction of movement of this element is perpendicular to the direction of the fluid flow, they can only be opened or closed completely; they cannot be used for regulation or throttling. Therefore, gate valves are not suitable for applications that require such functions, and they are generally manual valves. 2. Ball valves are characterized by their compact structure, reliable sealing, simplicity, and ease of maintenance. The sealing surface and the ball itself remain in a closed state, making them resistant to erosion by the fluid. They are easy to operate and maintain, and are suitable for use with various fluids such as water, solvents, acids, and natural gas. They can also handle fluids under harsh working conditions and withstand high pressure differences, which is why they are increasingly widely used. 3. Butterfly valves are suitable for use in pipelines that transport various corrosive and non-corrosive fluid media; they are used to regulate and stop the flow of these media. They can be used in situations with high pressure differences, and their diameter can also be made quite large. There are many types of valves; in addition to the three mentioned above, there are also eccentric rotary valves, sleeve valves, single-seat valves, double-seat valves, diaphragm valves, angle valves, tee valves, and so on. There are also various types of actuators, such as pneumatic ones, electric ones, pneumatic diaphragm actuators, cylinders, etc. Valves constitute a vast field of study, and you can take a look at books related to valves.

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We can no longer reward with wealth, but thank you anyway.

A gate valve is a type of valve in which the closing element (gate) moves vertically along the center line of the passage. Gate valves are primarily used for shutting off flow in pipelines. Globe valves are a widely used type of valve; they are typically chosen for cutting-off devices with a diameter of DN≥50mm. Sometimes, globe valves are also used for cutting-off devices with much smaller diameters. Globe valves have the following advantages: ① Low fluid resistance. ②A small external force is required to open and close it. ③The flow direction of the medium is not restricted. ④When fully open, the sealing surface is subject to less erosion by the working medium compared to a globe valve. ⑤Its shape is relatively simple, and it has good castability. Globe valves also have their drawbacks: ① They have large external dimensions and an elevated opening height. It requires a large amount of space for installation. ②During opening and closing, there is relative friction between the sealing surfaces, which can easily lead to scuffing. ③Gate valves generally have two sealing surfaces, which adds some difficulty to processing, grinding, and maintenance. A globe valve is a valve in which the closing element (valve disc) moves along the center line of the valve seat. Stop valves are primarily used for shutting off flow in pipelines. Globe valves have the following advantages: 1. During opening and closing, the frictional force on the sealing surface is lower than that of gate valves, making them more wear-resistant. 2. The opening height is small. 3. There is usually only one sealing surface, the manufacturing process is simple, and it is easy to maintain. Ball valves and plug valves belong to the same type of valve; the only difference is that their closing element is a sphere, which rotates around the axis of the valve body to enable opening and closing. Ball valves are primarily used in pipelines to cut off flow, distribute it, and change the direction of the fluid flow. Ball valves are a new type of valve that has been widely used in recent years. They possess the following advantages: 1. Low fluid resistance, with a resistance coefficient equal to that of a pipe section of the same length. 2. Simple structure, small size, and light weight. 3. Tight and reliable: Currently, plastic is widely used as the material for the sealing surfaces of ball valves, providing good sealing performance; they are also extensively used in vacuum systems. 4. It is easy to operate and opens/closes quickly – only 90° of rotation is required to go from fully open to fully closed, facilitating remote control. 5. It is easy to maintain; the ball valve has a simple structure, and the sealing rings are usually movable, making it convenient to remove and replace them. 6. When fully open or fully closed, the sealing surfaces of the ball and the valve seat are separated from the medium; thus, as the medium passes through, it does not cause erosion of the valve’s sealing surfaces. 7. It has a wide range of applications, with diameters ranging from a few millimeters to several meters, and it can be used in conditions ranging from high vacuum to high pressure. Ball valves are widely used in various industries such as petroleum, chemicals, power generation, papermaking, nuclear energy, aviation, and rockets, as well as in people’s daily lives. A valve in which the disc rotates around a fixed axis within the valve body is called a butterfly valve. 1. As a sealed butterfly valve, it saw rapid development only after the advent of synthetic rubber; therefore, it is a new type of shut-off valve. In our country, until the 1980s, butterfly valves were mainly used for low-pressure applications, with synthetic rubber being used for the valve seats. In the 1990s, due to increased exchanges with foreign countries, hard-sealed (metal-sealed) butterfly valves saw rapid development. Currently, several valve manufacturers are able to produce medium-pressure metal-sealed butterfly valves steadily, thereby expanding the range of applications for these butterfly valves. 2. The media that butterfly valves can transport and control include water, condensed water, circulating water, sewage, seawater, air, gas, liquefied natural gas, dry powder, slurry, fruit pulp, and mixtures containing suspended solids.