Views: 269 Author: Site Editor Publish Time: 2021-11-16 Origin: Site
Gate valve and butterfly valves are used as switches and used in the pipeline to regulate the flow. Certainly, there are many kinds of butterfly valves like pneumatic butterfly valve. How to choose the butterfly valve and gate valve? There are some methods.
In the water supply network, to reduce the soil depth of the pipeline, the butterfly valve is usually selected for the larger diameter pipeline. If it has little effect on the soil depth, gate valve is usually selected. However, the price of a gate valve with the same scale is higher than that of a butterfly valve. As for the demarcation line of caliber, it should be considered according to the specific situation. Hence, on different occasions, we should choose different valves such as butterfly valve with pneumatic actuator. In recent ten years, the failure of butterfly valve is higher than that of gate valve. Therefore, it is worthy of attention to expanding the application scope of gate valve-like true union gate valve when conditions permit.
Because the flow direction of the gate valve plate and the medium is vertical, the gate valve has small flow resistance and good sealing performance. If the nickel-plated brass ball valve is not operated in place on the valve plate, the erosion of the medium on the valve plate will make the valve plate vibrate, and the seal of the gate valve will be easily damaged.
A butterfly valve, also known as a flap valve, is a control valve with a simple structure, for example, stainless steel butterfly valve, which can be used for low-pressure pipeline medium on-off control. A Butterfly valve refers to a kind of valve whose closing piece (butterfly valve disc or butterfly plate) is a disc and rotates around the valve shaft to open and close. The valve can be used to control air, water, steam, various corrosive media, mud, oil, liquid metal, and radioactive media, etc. And the gas butterfly valve is good at that. It is mainly used to cut off and throttle the pipeline. The opening and closing part of the butterfly valve is a disc-shaped butterfly plate, which rotates around its axis, to achieve the purpose of opening and closing or adjustment.
The butterfly plate of air actuated butterfly valve is driven by the valve stem and can be opened and closed once if it is turned 90 degrees. The flow of the medium can be controlled by changing the deflection angle of the butterfly plate.
A butterfly valve is applies to the pipeline conveying various corrosive and non-corrosive fluid medium in the coal, natural gas, city gas, cold and hot air, chemical smelting and building water supply and drainage, etc., which is used to regulate the flow of the medium.
A gate valve is a kind of gate, whose movement direction is perpendicular to the fluid direction. A gate valve can only be fully opened and fully closed. There is a kind of gate is called an elastic gate.
When the gate valve is closed, the sealing surface can only rely on the medium pressure to seal. That is, with the help of the medium pressure to press the sealing surface of the gate valve to the seat on the other side it can seal the surface, which is self-sealing. Most gate valves are sealed compulsorily. When the valve is closed, the gate should be forced to the valve seat by an external force, to ensure the tightness of the surface.
Gate valve plate does linear motion with the stem, also known as a rising stem gate valve. Generally, there are trapezoidal threads on the lifting rod. Through the nut on the top of the valve and the guide groove on the valve body, the rotary motion is changed into linear motion. When the valve is opened and the lifting height of the ram is equal to 1:1 of the valve diameter, the fluid channel is completely unblocked, but in operation, this position cannot be monitored. The apex of the valve stem is used as the mark, and the position that can not be opened is used as its fully open position. Taking into consideration temperature change, usually, it is at the top position, and then back 1 / 2-1 turn. Therefore, the fully open position of the valve is determined by the position of the RAM. Some gate valve stem nut is set on the gate, the hand-wheel rotation driving the stem to rotate so that the gate is lifted. This kind of valve is called a rotary stem gate valve or non-rising stem gate valve.
