Focus On Triple Offset Butterfly Valve 

The difference between butterfly valve and gate valve

1.First distinguish by definition:

Gate valve is one of the most common opening and closing valves. It uses the gate (ie, the opening and closing parts, in the gate, the opening and closing parts are called gates or gates, and the gate seat is called the gate seat) to connect (fully open) or Cuts off (fully shuts off) the medium in the line. It is not allowed to be used as a shut-off, and it should be avoided to slightly open the gate during use, because the erosion of the high-speed flowing medium will accelerate the damage of the sealing surface. The gate plate acts as a lifting motion on the side perpendicular to the center line of the gate seat channel, cutting off the medium in the pipeline like a gate, so it is called a gate valve.

Butterfly valve refers to a kind of valve whose closing member (valve disc or butterfly plate) is a disc and rotates around the valve shaft to achieve opening and closing. It is mainly used for cutting off and throttling on the pipeline. The butterfly valve opening and closing part is a disc-shaped butterfly plate, which rotates around its own axis in the valve body to achieve the purpose of opening and closing or adjustment. The butterfly valve is usually less than 90° from fully open to fully closed. The butterfly valve and the butterfly stem have no self-locking ability. For the positioning of the butterfly plate, a worm gear reducer should be installed on the valve stem. The use of worm gear reducer can not only make the butterfly plate have self-locking ability, so that the butterfly plate can stop at any position, but also improve the operation performance of the valve.

The difference between butterfly valve and gate valve

2.Secondly, in terms of the way of action:
The gate valve is a straight-stroke valve, that is, the valve stem drives the valve plate to move vertically up and down to complete the opening and closing of the gate valve, so 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 belongs 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 opening height of the butterfly valve is only one quarter of the diameter of the channel, so it opens and closes quickly.

The difference between butterfly valve and gate valve 2

3.According to the functions and uses of gate valves and butterfly valves:

The gate valve has small flow resistance and good sealing performance. Because the valve plate of the gate valve and the flow direction of the medium are at a vertical angle, if the gate valve is not switched in place on the valve plate, the scouring of the medium on the valve plate will cause the valve plate to vibrate, and it is easy to damage the seal of the gate valve. Therefore, it is mostly used as a cut-off for pipelines that require strict sealing and do not need frequent opening and closing, and is not suitable for adjusting the parameters of the pipeline medium.

Due to the slow opening and closing speed, it is not suitable for emergency cut-off. The gate valve has a wide range of working conditions and can be used in high temperature, low temperature, high pressure, low pressure and other working conditions.

The butterfly valve not only has the function of cut-off, but also has the function of adjustment. The butterfly valve opens and closes quickly and can be opened and closed frequently. It is especially suitable for occasions requiring rapid opening or closing. Compared with the gate valve, the butterfly valve is small in size, light in weight and cheap in price. In some working conditions with limited installation space, the butterfly valve with wafer connection can be selected, which saves more space.

Therefore, it can be made into a large diameter, and butterfly valves above DN300 are used more. And it can be used to transport unclean medium pipelines containing small particles. However, the pressure and temperature range used by the butterfly valve is small, and the sealing performance is not as good as that of the gate valve. The price of butterfly valves of the same diameter is much lower than that of gate valves.

In many working conditions, butterfly valves gradually replace other types of valves and become the first choice of many users. The main difference between gate valve and butterfly valve is that the gate valve has no adjustment function and the butterfly valve has the adjustment function.

4.Finally, from the perspective of the price of the two:

The price of the electric butterfly valve is cheap, the price of the electric gate valve is high, and the diameter of the butterfly valve can be made large, but the gate valve is relatively useless. , The sealing of gate valve is better than that of butterfly valve. Most of butterfly valves are mainly soft seal, and their temperature resistance is not as good as gate valve.

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