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Why do people use ball valves or butterfly valves instead of gate valves?

Among many valve products, gate valves, butterfly valves and ball valves are very common valve types. However, many users do not know what is the difference between them when they are selected, but do not know how to choose.

The gate valve is one of the most common on-off valves. It is connected (opened) by means of a shutter (is, the opening and closing member, the opening and closing member in the gate is called a gate or gate, and the gate is called a gate seat). Truncate (fully close) the media in the pipeline.

A butterfly valve is a type of valve in which the closing member (valve or disc) is a disc that rotates around the valve shaft to open and close, and is mainly used for cutting and throttling on the pipeline.

The ball valve works by rotating the valve plug to make the valve unblocked or occluded. The ball valve switch is light in weight, small in size, can be made into a large diameter, reliable in sealing, simple in structure, convenient in maintenance, and the sealing surface and the spherical surface are often closed, and is not easily eroded by the medium, and is widely used in various industries.

Ball Valve

The gate valve is a straight-stroke valve, that is, the valve stem drives the valve plate to move up and down vertically. When the gate valve is opened and closed, the flow resistance of the gate valve is small, but because of its high opening height, the opening and closing speed is slow. The butterfly valve and the ball valve belong to the angular stroke valve, that is, the valve plate of the butterfly valve rotates 90° around the valve shaft to complete the opening and closing action of the butterfly valve. Therefore, the butterfly valve opening height is only one quarter of the diameter of the channel, so the opening and closing is rapid. The gate valve has small flow resistance and good sealing performance. Because the gate valve and the medium flow direction are vertical angles, if the gate valve is not in place in the valve plate switch, the medium slams the valve plate to make the valve plate vibrate, which is easy to be sealed as a gate valve. Therefore, it is often used for pipes that require strict sealing and does not require frequent opening and closing, and is not suitable for adjusting the parameters of the pipe medium. Due to the slow opening and closing speed of the gate valve, it is not suitable for emergency cutting. The butterfly valve not only has a cut-off effect, but also has an adjustment function. The butterfly valve opens and closes quickly and can be frequently opened and closed. It is especially suitable for applications requiring quick opening or cutting. Compared with the gate valve, the butterfly valve has small size and light weight. In some working conditions with limited installation space, the butterfly valve with clip-on connection can be selected to save space. The butterfly valve can be made into a large diameter, and the butterfly valve above DN300 is used more. The price of a butterfly valve of the same diameter is much lower than that of a gate valve. The ball valve is wiping during opening and closing, so it can be used in media with suspended solid particles. The ball valve has a small fluid resistance, and the full-bore ball valve has substantially no flow resistance.

In many working conditions, butterfly valves and ball valves have gradually replaced other types of valves, making them the first choice for many users.