The butterfly plate of the butterfly valve is installed in the diameter direction of the pipeline. In the cylindrical channel of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis at an angle between 0 ° and 90 °. When it rotates to 90 °, the valve is fully open. Butterfly valves have a simple structure, small size, and light weight, consisting of only a few components. And it can be quickly opened and closed by simply rotating 90 °, with simple operation, and the valve has good fluid control characteristics. When the butterfly valve is in the fully open position, the thickness of the butterfly plate is the only resistance for the medium to flow through the valve body. Therefore, the pressure drop generated by this valve is very small, and it has good flow control characteristics. Butterfly valves have two sealing types: elastic sealing and metal sealing. Elastic sealing valve, the sealing ring can be embedded on the valve body or attached around the butterfly plate. Valves with metal seals generally have a longer lifespan than those with elastic seals, but it is difficult to achieve complete sealing. Metal seals can adapt to higher operating temperatures, while elastic seals have the drawback of being limited by temperature. If butterfly valves are required for flow control, the main thing is to choose the correct size and type of valve. The structural principle of butterfly valves is particularly suitable for making large-diameter valves. Butterfly valves are not only widely used in general industries such as petroleum, gas, chemical, and water treatment, but also in the cooling water system of thermal power plants.

There are two commonly used butterfly valves: clamp type butterfly valve and flange type butterfly valve. The clamp type butterfly valve is connected between two pipeline flanges with double headed bolts. The flange type butterfly valve has a flange on the valve, and the flanges on both ends of the valve are connected to the pipeline flange with bolts.

1、 Purpose:

Used for gas pipelines in the sulfuric acid industry: inlet and outlet of furnace front blower, inlet and outlet of relay blower, series and connecting valves for electric mist removal, inlet and outlet of S02 main blower, converter adjustment, preheater inlet and outlet, etc., for regulating and cutoff gas volume. Used in the sulfur burning, conversion, and dry absorption sections of sulfur based sulfuric acid systems, it is the preferred brand of valves for sulfur based sulfuric acid plants. It is widely regarded by users as a butterfly valve with good sealing performance, light operation, secondary corrosion, high temperature resistance, easy and flexible operation, and safe and reliable use. It has been widely promoted and used.

It is also widely used as a regulating and shut-off device in pipelines for media such as SO2, steam, air, coal gas, ammonia, CO2 gas, oil products, water, salt water, alkali solution, seawater, nitric acid, hydrochloric acid, sulfuric acid, phosphoric acid, etc. in industries such as chemical, petrochemical, smelting, pharmaceutical, and food.

Structural Features

① The unique design of three-way eccentricity ensures frictionless transmission between the sealing surfaces, extending the service life of the valve.

② Elastic sealing is generated by torque.

③ The clever wedge-shaped design enables the valve to have an automatic sealing function that becomes tighter as it is closed, with compensatory and zero leakage between the sealing surfaces.

④ Small size, light weight, easy operation, and convenient installation.

⑤ Pneumatic and electric devices can be configured according to user requirements to meet the needs of remote control and program control.

⑥ Changing the material of the parts can be applied to various media and can be used for lining anti-corrosion (lining F46, GXPP, PO, etc.).

⑦ Diversified continuous structures: clamps, flanges, and butt welds.

The butterfly valve opening and closing component is a disc-shaped butterfly plate that rotates around its own axis inside the valve body to achieve opening, closing, or regulating of the valve, which is called a butterfly valve. The fully open and fully closed butterfly valve is usually less than 900, and the butterfly valve and stem themselves do not have strong self-locking force. In order to position the butterfly plate, a worm gear reducer should be installed on the stem. By using a worm gear reducer, not only can the butterfly plate have self-locking ability to stop at any position, but it can also improve the operational performance of the valve. The characteristics of industrial butterfly valves are high temperature resistance, high pressure range, large nominal diameter, carbon steel valve body, and metal ring instead of rubber ring for valve plate sealing. Large high-temperature butterfly valves are manufactured by welding steel plates and are mainly used for flue gas ducts and gas pipelines for high-temperature media.

Advantages of butterfly valves

Easy and quick opening and closing, labor-saving, low fluid resistance, and can be operated frequently. Simple structure, small size, and light weight. It can transport mud with minimal liquid accumulation at the pipeline outlet. Under low pressure, good sealing can be achieved. Good regulation performance.

Disadvantages of butterfly valves

1. The pressure and working temperature range are small. 2. Poor sealing performance. Butterfly valves can be divided into offset plate, vertical plate, inclined plate, and lever type according to their structural forms. According to the sealing form, it can be divided into two types: relatively sealed type and hard sealed type. Soft sealing type generally uses rubber ring sealing, while hard sealing type usually uses metal ring sealing. According to the connection type, it can be divided into flange connection and clamp connection; According to the transmission mode, it can be divided into manual, gear transmission, pneumatic, hydraulic, and electric.

Butterfly valve classification

According to the structural form, it can be divided into offset plate, vertical plate, inclined plate, and lever type. According to the sealing form, it can be divided into two types: relatively sealed type and hard sealed type. Soft sealing type generally uses rubber ring sealing, while hard sealing type usually uses metal ring sealing. According to the connection type, it can be divided into flange connection and clamp connection; According to the transmission mode, it can be divided into manual, gear transmission, pneumatic, hydraulic, and electric.

Butterfly valve installation and maintenance matters

During installation, the valve disc should be stopped in the closed position. The opening position should be determined according to the rotation angle of the butterfly plate. Butterfly valves with bypass valves should be installed according to the manufacturer's installation instructions before opening. For heavy butterfly valves, a solid foundation should be established.

material

1. Valve body material: gray cast iron, ductile iron, cast steel, aluminum alloy, stainless steel, etc;

2. Valve plate material: duplex stainless steel, nylon 11 plate, galvanized plate, aluminum bronze;

3. Valve seat material: Nitrile rubber, EPDM rubber, Fluororubber, Silicone rubber, PTFE